CyberSecBulletin
CVE-2024-53174NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-53174 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 e9be26735d055c42543a4d047a769cc6d0fb1504, 02999e135b013d85c6df738746e8e24699befee4, c7dac3af57e38b2054f990e573256d90bf887958 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 0.26% 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 e9be26735d055c42543a4d047a769cc6d0fb1504 or 02999e135b013d85c6df738746e8e24699befee4 or c7dac3af57e38b2054f990e573256d90bf887958 or 068c0b50f3f700b94f78850834cd91ae3b34c2c1, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.287 or 5.10.231 or 5.15.174 or 6.1.120, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxd48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, e9be26735d055c42543a4d047a769cc6d0fb1504; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, 02999e135b013d85c6df738746e8e24699befee4; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, c7dac3af57e38b2054f990e573256d90bf887958; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, 068c0b50f3f700b94f78850834cd91ae3b34c2c1; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, acfaf37888e0f0732fb6a50ff093dce6d99994d0; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, ec305f303bf070b4f6896b7a76009f702956d402; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, d882e2b7fad3f5e5fac66184a347f408813f654a; d48cf356a13073853f19be6ca5ebbecfc2762ebe up to, but not including, 2862eee078a4d2d1f584e7f24fa50dddfa5f3471; and 1 more rangese9be26735d055c42543a4d047a769cc6d0fb1504, 02999e135b013d85c6df738746e8e24699befee4, c7dac3af57e38b2054f990e573256d90bf887958, 068c0b50f3f700b94f78850834cd91ae3b34c2c1, acfaf37888e0f0732fb6a50ff093dce6d99994d0, ec305f303bf070b4f6896b7a76009f702956d402
LinuxLinux Kernelbefore 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, 6.12.25.4.287, 5.10.231, 5.15.174, 6.1.120, 6.6.64, 6.11.11

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 CISA (ADP).

Official description

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: make sure cache entry active before cache_show The function `c_show` was called with protection from RCU. This only ensures that `cp` will not be freed. Therefore, the reference count for `cp` can drop to zero, which will trigger a refcount use-after-free warning when `cache_get` is called. To resolve this issue, use `cache_get_rcu` to ensure that `cp` remains active. ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 7 PID: 822 at lib/refcount.c:25 refcount_warn_saturate+0xb1/0x120 CPU: 7 UID: 0 PID: 822 Comm: cat Not tainted 6.12.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb1/0x120 Call Trace: <TASK> c_show+0x2fc/0x380 [sunrpc] seq_read_iter+0x589/0x770 seq_read+0x1e5/0x270 proc_reg_read+0xe1/0x140 vfs_read+0x125/0x530 ksys_read+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e

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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