CyberSecBulletin
CVE-2024-53173NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-53173 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 1cfae9575296f5040cdc84b0730e79078c081d2d, 7bf6bf130af8ee7d93a99c28a7512df3017ec759, 5237a297ffd374a1c4157a53543b7a69d7bbbc03 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 0.27% 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 1cfae9575296f5040cdc84b0730e79078c081d2d or 7bf6bf130af8ee7d93a99c28a7512df3017ec759 or 5237a297ffd374a1c4157a53543b7a69d7bbbc03 or 2ab9639f16b05d948066a6c4cf19a0fdc61046ff, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 4.19.325 or 5.4.287 or 5.10.231 or 5.15.174, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, 1cfae9575296f5040cdc84b0730e79078c081d2d; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, 7bf6bf130af8ee7d93a99c28a7512df3017ec759; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, 5237a297ffd374a1c4157a53543b7a69d7bbbc03; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, 2ab9639f16b05d948066a6c4cf19a0fdc61046ff; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, ba6e6c04f60fe52d91520ac4d749d372d4c74521; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, 229a30ed42bb87bcb044c5523fabd9e4f0e75648; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, e2277a1d9d5cd0d625a4fd7c04fce2b53e66df77; 24ac23ab88df5b21b5b2df8cde748bf99b289099 up to, but not including, b56ae8e715557b4fc227c9381d2e681ffafe7b15; and 2 more ranges1cfae9575296f5040cdc84b0730e79078c081d2d, 7bf6bf130af8ee7d93a99c28a7512df3017ec759, 5237a297ffd374a1c4157a53543b7a69d7bbbc03, 2ab9639f16b05d948066a6c4cf19a0fdc61046ff, ba6e6c04f60fe52d91520ac4d749d372d4c74521, 229a30ed42bb87bcb044c5523fabd9e4f0e75648
LinuxLinux Kernel2.6.16 up to, but not including, 4.19.325; 4.20 up to, but not including, 5.4.287; 5.5 up to, but not including, 5.10.231; 5.11 up to, but not including, 5.15.174; 5.16 up to, but not including, 6.1.120; 6.2 up to, but not including, 6.6.64; 6.7 up to, but not including, 6.11.11; 6.12 up to, but not including, 6.12.24.19.325, 5.4.287, 5.10.231, 5.15.174, 6.1.120, 6.6.64

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 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)

Official description

In the Linux kernel, the following vulnerability has been resolved: NFSv4.0: Fix a use-after-free problem in the asynchronous open() Yang Erkun reports that when two threads are opening files at the same time, and are forced to abort before a reply is seen, then the call to nfs_release_seqid() in nfs4_opendata_free() can result in a use-after-free of the pointer to the defunct rpc task of the other thread. The fix is to ensure that if the RPC call is aborted before the call to nfs_wait_on_sequence() is complete, then we must call nfs_release_seqid() in nfs4_open_release() before the rpc_task is freed.

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: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use After Free vulnerabilities

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