CyberSecBulletin
CVE-2022-3534NVD status: Modified

Kernel: Use After Free

CVE-2022-3534 is a high-severity use after free vulnerability in Kernel from Linux, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited from the same local network by an attacker with a low-privileged account, without any action from a user. Affected Kernel versions: 5.10.162; 5.15.0; 5.15.1, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.96% chance of exploitation within 30 days, higher than 62% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1 or a later version.
  2. Update Linux Kernel to 5.10.163 or 5.15.86 or 6.0.16 or 6.1.2, whichever matches your release line, or a later version.
  3. Read the advisory on git.kernel.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxKernel5.10.162; 5.15.0; 5.15.1; 5.15.2; 5.15.3; 5.15.4; 5.15.5; 5.15.6; and 32 more rangesNot stated
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1V1.1
DebianDebian Linux11.0Not stated
LinuxLinux Kernel5.10 up to, but not including, 5.10.163; 5.11 up to, but not including, 5.15.86; 5.16 up to, but not including, 6.0.16; 6.1 up to, but not including, 6.1.25.10.163, 5.15.86, 6.0.16, 6.1.2

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.05.1MediumCNA (vuldb.com)
CVSS 3.15.5MediumCNA (vuldb.com)
CVSS 3.18.0HighNVD
CVSS 2.04.9MediumCNA (vuldb.com)

Official description

A vulnerability has been found in Linux Kernel up to 5.10.162/5.15.85/6.0.15/6.1.1. The impacted element is the function btf_dump_name_dups of the file tools/lib/bpf/btf_dump.c of the component libbpf. The manipulation leads to use after free. Upgrading to version 5.10.163, 5.15.86, 6.0.16, 6.1.2 and 6.2 is sufficient to resolve this issue. The identifier of the patch is c61650b869e0b6fb0c0a28ed42d928eea969afc8/fbe08093fb2334549859829ef81d42570812597d/8c64a8e76eb85d422af5ec60ccbf26e3ead8c333/a733bf10198eb5bb927890940de8ab457491ed3b/93c660ca40b5d2f7c1b1626e955a8e9fa30e0749. You should upgrade the affected component.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Kernel

All Kernel vulnerabilities

Recent Use After Free vulnerabilities

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