high
8.8
CWE
119
Advisory Published
CVE Published
Updated

CVE-2021-25217: A buffer overrun in lease file parsing code can be used to exploit a common vulnerability shared by dhcpd and dhclient

First published: Fri May 21 2021(Updated: )

A flaw was found in the Dynamic Host Configuration Protocol (DHCP). There is a discrepancy between the code that handles encapsulated option information in leases transmitted "on the wire" and the code which reads and parses lease information after it has been written to disk storage. This flaw allows an attacker to deliberately cause a situation where dhcpd while running in DHCPv4 or DHCPv6 mode, or the dhclient attempts to read a stored lease that contains option information, to trigger a stack-based buffer overflow in the option parsing code for colon-separated hex digits values. The highest threat from this vulnerability is to data confidentiality and integrity as well as service availability.

Credit: security-officer@isc.org

Affected SoftwareAffected VersionHow to fix
redhat/dhcp<12:4.1.1-64.P1.el6_10
12:4.1.1-64.P1.el6_10
redhat/dhcp<12:4.2.5-83.el7_9.1
12:4.2.5-83.el7_9.1
redhat/dhcp<12:4.2.5-42.el7_2.2
12:4.2.5-42.el7_2.2
redhat/dhcp<12:4.2.5-47.el7_3.2
12:4.2.5-47.el7_3.2
redhat/dhcp<12:4.2.5-58.el7_4.5
12:4.2.5-58.el7_4.5
redhat/dhcp<12:4.2.5-69.el7_6.1
12:4.2.5-69.el7_6.1
redhat/dhcp<12:4.2.5-77.el7_7.1
12:4.2.5-77.el7_7.1
redhat/dhcp<12:4.3.6-44.el8_4.1
12:4.3.6-44.el8_4.1
redhat/dhcp<12:4.3.6-34.el8_1.2
12:4.3.6-34.el8_1.2
redhat/dhcp<12:4.3.6-40.el8_2.2
12:4.3.6-40.el8_2.2
redhat/cri-o<0:1.20.3-6.rhaos4.7.git0d0f863.el8
0:1.20.3-6.rhaos4.7.git0d0f863.el8
redhat/dhcp<12:4.3.6-41.el8_3.1
12:4.3.6-41.el8_3.1
redhat/openshift-clients<0:4.7.0-202106252127.p0.git.8b4b094.el7
0:4.7.0-202106252127.p0.git.8b4b094.el7
redhat/openshift-kuryr<0:4.7.0-202106232224.p0.git.c7654fb.el8
0:4.7.0-202106232224.p0.git.c7654fb.el8
redhat/polkit<0:0.115-11.el8_3.2
0:0.115-11.el8_3.2
redhat/redhat-virtualization-host<0:4.3.16-20210615.0.el7_9
0:4.3.16-20210615.0.el7_9
redhat/dhcp<4.4.2
4.4.2
redhat/dhcp<4.1
4.1
ISC DHCP Server>=4.4.0<=4.4.2
ISC DHCP Server=4.1-esv-r1
ISC DHCP Server=4.1-esv-r10
ISC DHCP Server=4.1-esv-r10_b1
ISC DHCP Server=4.1-esv-r10_rc1
ISC DHCP Server=4.1-esv-r10b1
ISC DHCP Server=4.1-esv-r10rc1
ISC DHCP Server=4.1-esv-r11
ISC DHCP Server=4.1-esv-r11_b1
ISC DHCP Server=4.1-esv-r11_rc1
ISC DHCP Server=4.1-esv-r11_rc2
ISC DHCP Server=4.1-esv-r11b1
ISC DHCP Server=4.1-esv-r11rc1
ISC DHCP Server=4.1-esv-r11rc2
ISC DHCP Server=4.1-esv-r12
ISC DHCP Server=4.1-esv-r12-p1
ISC DHCP Server=4.1-esv-r12_b1
ISC DHCP Server=4.1-esv-r12_p1
ISC DHCP Server=4.1-esv-r12b1
ISC DHCP Server=4.1-esv-r13
ISC DHCP Server=4.1-esv-r13_b1
ISC DHCP Server=4.1-esv-r13b1
ISC DHCP Server=4.1-esv-r14
ISC DHCP Server=4.1-esv-r14_b1
ISC DHCP Server=4.1-esv-r14b1
ISC DHCP Server=4.1-esv-r15
ISC DHCP Server=4.1-esv-r15-p1
ISC DHCP Server=4.1-esv-r15_b1
ISC DHCP Server=4.1-esv-r16
Fedora=33
Fedora=34
Debian=9.0
siemens ruggedcom rox rx1400 firmware<2.15.0
Siemens RUGGEDCOM ROX RX1400
Siemens Ruggedcom ROX RX1500 Firmware>=2.3.0<2.15.0
Siemens RUGGEDCOM ROX RX1500
Siemens Ruggedcom Rox RX1501 Firmware>=2.3.0<2.15.0
RUGGEDCOM ROX RX1501
Siemens Ruggedcom ROX RX1510 Firmware>=2.3.0<2.15.0
Siemens RUGGEDCOM ROX RX1510
Siemens Ruggedcom ROX RX1511 Firmware>=2.3.0<2.15.0
Siemens RUGGEDCOM ROX RX1511
Siemens Ruggedcom ROX RX1512 Firmware>=2.3.0<2.15.0
Siemens RUGGEDCOM ROX RX1512
Siemens Ruggedcom ROX RX1524 Firmware<2.15.0
Siemens Ruggedcom ROX RX1524 Firmware
Siemens Ruggedcom ROX RX1536 Firmware<2.15.0
Siemens Ruggedcom ROX RX1536 Firmware
Siemens Ruggedcom ROX RX5000 Firmware>=2.3.0<2.15.0
Siemens Ruggedcom ROX RX5000 Firmware
Siemens RUGGEDCOM ROX MX5000RE firmware>=2.3.0<2.15.0
Siemens RUGGEDCOM ROX MX5000
NetApp ONTAP Select Deploy
netapp solidfire \& hci management node
siemens sinec ins<1.0
siemens sinec ins=1.0
siemens sinec ins=1.0-sp1

Remedy

http://www.openwall.com/lists/oss-security/2021/05/26/6

Remedy

https://cert-portal.siemens.com/productcert/pdf/ssa-406691.pdf

Remedy

https://cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf

Remedy

Upgrade to the patched release most closely related to your current version of ISC DHCP: ISC DHCP 4.1-ESV-R16-P1 ISC DHCP 4.4.2-P1

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2021-25217?

    CVE-2021-25217 is classified as a moderate severity vulnerability.

  • How do I fix CVE-2021-25217?

    To mitigate CVE-2021-25217, upgrade the DHCP package to the appropriate versions specified in the advisory.

  • Which systems are affected by CVE-2021-25217?

    CVE-2021-25217 affects multiple versions of the ISC DHCP server and related software packages.

  • Can CVE-2021-25217 lead to data loss?

    Yes, CVE-2021-25217 can potentially lead to data loss due to discrepancies in the handling of lease information.

  • Is CVE-2021-25217 exploitable remotely?

    CVE-2021-25217 can be exploited remotely, allowing an attacker to manipulate DHCP lease information.

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