CyberSecBulletin
CVE-2024-35789NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-35789 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions ea9a0cfc07a7d3601cc680718d9cff0d6927a921, be1dd9254fc115321d6fbee042026d42afc8d931, e8b067c4058c0121ac8ca71559df8e2e08ff1a7e as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to ea9a0cfc07a7d3601cc680718d9cff0d6927a921 or be1dd9254fc115321d6fbee042026d42afc8d931 or e8b067c4058c0121ac8ca71559df8e2e08ff1a7e or c8bddbd91bc8e42c961a5e2cec20ab879f21100f, whichever matches your release line, or a later version.
  2. Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1.1 or a later version.
  3. Update Linux Kernel to 4.15 or 4.19.312 or 5.4.274 or 5.10.215, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxa7f1721684628b8ae6015bca9a176046ee6f30cc up to, but not including, ea9a0cfc07a7d3601cc680718d9cff0d6927a921; bd7e90c82850f49c23004d54de14e46d373748a6 up to, but not including, be1dd9254fc115321d6fbee042026d42afc8d931; cc413b375c6d95e68a4629cb1ba9d099de78ebb9 up to, but not including, e8b067c4058c0121ac8ca71559df8e2e08ff1a7e; dd0b45538146cb6a54d6da7663b8c3afd16ebcfd up to, but not including, c8bddbd91bc8e42c961a5e2cec20ab879f21100f; dd0b45538146cb6a54d6da7663b8c3afd16ebcfd up to, but not including, 7eeabcea79b67cc29563e6a9a5c81f9e2c664d5b; dd0b45538146cb6a54d6da7663b8c3afd16ebcfd up to, but not including, 6b948b54c8bd620725e0c906e44b10c0b13087a7; dd0b45538146cb6a54d6da7663b8c3afd16ebcfd up to, but not including, 2884a50f52313a7a911de3afcad065ddbb3d78fc; dd0b45538146cb6a54d6da7663b8c3afd16ebcfd up to, but not including, e8678551c0243f799b4859448781cbec1bd6f1cb; and 9 more rangesea9a0cfc07a7d3601cc680718d9cff0d6927a921, be1dd9254fc115321d6fbee042026d42afc8d931, e8b067c4058c0121ac8ca71559df8e2e08ff1a7e, c8bddbd91bc8e42c961a5e2cec20ab879f21100f, 7eeabcea79b67cc29563e6a9a5c81f9e2c664d5b, 6b948b54c8bd620725e0c906e44b10c0b13087a7
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1.1V1.1.1
LinuxLinux Kernel4.14.232 up to, but not including, 4.15; 4.19.189 up to, but not including, 4.19.312; 5.4.114 up to, but not including, 5.4.274; 5.10.32 up to, but not including, 5.10.215; 5.11.16 up to, but not including, 5.12; 5.12.1 up to, but not including, 5.15.154; 5.16 up to, but not including, 6.1.84; 6.2 up to, but not including, 6.6.24; and 4 more ranges4.15, 4.19.312, 5.4.274, 5.10.215, 5.12, 5.15.154
DebianDebian Linux10.0Not stated

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
LocalThe attacker needs local access or must trick a user into running something.
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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.0HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: check/clear fast rx for non-4addr sta VLAN changes When moving a station out of a VLAN and deleting the VLAN afterwards, the fast_rx entry still holds a pointer to the VLAN's netdev, which can cause use-after-free bugs. Fix this by immediately calling ieee80211_check_fast_rx after the VLAN change.

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

Recent Use After Free vulnerabilities

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