CVE-2021-0920: Android Kernel Race Condition Vulnerability
First published: Wed Jul 28 2021(Updated: )
A flaw was found in the linux kernel, unix_gc() assumes that candidate sockets can never gain an external reference (i.e. be installed into an fd) while the unix_gc_lock is held. Except for MSG_PEEK this is guaranteed by modifying inflight count under the unix_gc_lock. References: <a href="https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cbcf01128d0a92e131bd09f1688fe032480b65ca">https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cbcf01128d0a92e131bd09f1688fe032480b65ca</a>
Credit: security@android.com security@android.com security@android.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| redhat/kernel | <0:2.6.32-754.47.1.el6 | 0:2.6.32-754.47.1.el6 |
| redhat/kernel-rt | <0:3.10.0-1160.59.1.rt56.1200.el7 | 0:3.10.0-1160.59.1.rt56.1200.el7 |
| redhat/kernel | <0:3.10.0-1160.59.1.el7 | 0:3.10.0-1160.59.1.el7 |
| redhat/kernel | <0:3.10.0-514.99.1.el7 | 0:3.10.0-514.99.1.el7 |
| redhat/kernel | <0:3.10.0-693.99.1.el7 | 0:3.10.0-693.99.1.el7 |
| redhat/kernel | <0:3.10.0-957.92.1.el7 | 0:3.10.0-957.92.1.el7 |
| redhat/kernel | <0:3.10.0-1062.66.1.el7 | 0:3.10.0-1062.66.1.el7 |
| redhat/kernel-rt | <0:4.18.0-348.20.1.rt7.150.el8_5 | 0:4.18.0-348.20.1.rt7.150.el8_5 |
| redhat/kernel | <0:4.18.0-348.20.1.el8_5 | 0:4.18.0-348.20.1.el8_5 |
| redhat/kernel | <0:4.18.0-147.64.1.el8_1 | 0:4.18.0-147.64.1.el8_1 |
| redhat/kernel-rt | <0:4.18.0-193.75.1.rt13.125.el8_2 | 0:4.18.0-193.75.1.rt13.125.el8_2 |
| redhat/kernel | <0:4.18.0-193.75.1.el8_2 | 0:4.18.0-193.75.1.el8_2 |
| redhat/kernel-rt | <0:4.18.0-305.40.1.rt7.112.el8_4 | 0:4.18.0-305.40.1.rt7.112.el8_4 |
| redhat/kernel | <0:4.18.0-305.40.1.el8_4 | 0:4.18.0-305.40.1.el8_4 |
| redhat/redhat-virtualization-host | <0:4.3.22-20220330.1.el7_9 | 0:4.3.22-20220330.1.el7_9 |
| Google Android | ||
| Debian Debian Linux | =9.0 | |
| redhat/kernel | <5.14 | 5.14 |
| IBM BM Security Guardium | <=11.3 | |
| IBM Security Guardium | <=11.4 | |
| IBM Security Guardium | <=11.5 | |
| Google Android | ||
| Android kernel | ||
| debian/linux | 5.10.223-1 5.10.226-1 6.1.115-1 6.1.119-1 6.12.6-1 |
Remedy
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
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Reference Links
- https://www.cve.org/CVERecord?id=CVE-2021-0920 https://nvd.nist.gov/vuln/detail/CVE-2021-0920 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cbcf01128d0a92e131bd09f1688fe032480b65ca
- https://bugzilla.redhat.com/show_bug.cgi?id=2031930
- https://access.redhat.com/errata/RHSA-2022:1417
- https://access.redhat.com/errata/RHSA-2022:0622
- https://access.redhat.com/errata/RHSA-2022:0592
- https://access.redhat.com/errata/RHSA-2022:0620
- https://access.redhat.com/errata/RHSA-2022:1106
- https://access.redhat.com/errata/RHSA-2022:1104
- https://access.redhat.com/errata/RHSA-2022:1107
- https://access.redhat.com/errata/RHSA-2022:1103
- https://access.redhat.com/errata/RHSA-2022:1324
- https://access.redhat.com/errata/RHSA-2022:1373
- https://access.redhat.com/errata/RHSA-2022:0819
- https://access.redhat.com/errata/RHSA-2022:0825
- https://access.redhat.com/errata/RHSA-2022:0849
- https://access.redhat.com/errata/RHSA-2022:0823
- https://access.redhat.com/errata/RHSA-2022:0851
- https://access.redhat.com/errata/RHSA-2022:0958
- https://access.redhat.com/errata/RHSA-2022:0629
- https://access.redhat.com/errata/RHSA-2022:0590
- https://access.redhat.com/errata/RHSA-2022:0636
- https://access.redhat.com/errata/RHSA-2022:0771
- https://access.redhat.com/errata/RHSA-2022:0772
- https://access.redhat.com/errata/RHSA-2022:0777
- https://access.redhat.com/errata/RHSA-2022:1263
- https://access.redhat.com/errata/RHSA-2022:0841
- https://access.redhat.com/security/cve/cve-2021-0920
- https://source.android.com/security/bulletin/2021-11-01
- https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html
- https://launchpad.net/bugs/cve/CVE-2021-0920
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cbcf01128d0a92e131bd09f1688fe032480b65ca
- https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=2047640
- https://exchange.xforce.ibmcloud.com/vulnerabilities/215673
- https://www.ibm.com/support/pages/node/6999317 (Advisory)
- https://android.googlesource.com/kernel/common/+/cbcf01128d0a92e131bd09f1688fe032480b65ca
- https://source.android.com/docs/security/bulletin/2021-11-01 (Advisory)
- https://nvd.nist.gov/vuln/detail/CVE-2021-0920
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-0920
- https://security-tracker.debian.org/tracker/CVE-2021-0920
- https://ubuntu.com/security/CVE-2021-0920
- https://git.kernel.org/linus/cbcf01128d0a92e131bd09f1688fe032480b65ca
- https://googleprojectzero.blogspot.com/2022/08/the-quantum-state-of-linux-kernel.html
- https://googleprojectzero.github.io/0days-in-the-wild//0day-RCAs/2021/CVE-2021-0920.html
Parent vulnerabilities
(Appears in the following advisories)
- RHSA-2022:1417
- RHSA-2022:0622
- RHSA-2022:0592
- RHSA-2022:0620
- RHSA-2022:1106
- RHSA-2022:1104
- RHSA-2022:1107
- RHSA-2022:1103
- RHSA-2022:1324
- RHSA-2022:1373
- RHSA-2022:0819
- RHSA-2022:0825
- RHSA-2022:0849
- RHSA-2022:0823
- RHSA-2022:0851
- RHSA-2022:0958
- RHSA-2022:0629
- RHSA-2022:0590
- RHSA-2022:0636
- RHSA-2022:0771
- RHSA-2022:0772
- RHSA-2022:0777
- RHSA-2022:1263
- RHSA-2022:0841
- IBM-6999317
- collector/redhat-cve
- agent/type
- agent/first-publish-date
- collector/launchpad-cve
- source/Launchpad
- collector/nvd-index
- agent/software-canonical-lookup-request
- agent/title
- agent/severity
- collector/redhat-bugzilla
- source/Red Hat
- alias/CVE-2021-0920
- agent/software-canonical-lookup
- agent/weakness
- agent/author
- collector/nvd-api
- source/NVD
- collector/nvd-cve
- collector/ibm-support
- source/IBM
- collector/mitre-cve
- source/MITRE
- collector/android-source
- source/Android
- agent/last-modified-date
- exploited/true
- collector/cisa-known-exploited
- source/CISA
- agent/references
- agent/remedy
- agent/tags
- collector/usn-cve
- source/Ubuntu
- agent/description
- agent/event
- collector/security-tracker-debian
- source/Debian
- agent/softwarecombine
- agent/trending
- package-manager/redhat
- vendor/google
- canonical/google android
- vendor/debian
- canonical/debian debian linux
- version/debian debian linux/9.0
- vendor/ibm
- canonical/ibm bm security guardium
- version/ibm bm security guardium/11.3
- canonical/ibm security guardium
- version/ibm security guardium/11.4
- version/ibm security guardium/11.5
- vendor/android
- canonical/android kernel
- package-manager/debian