CyberSecBulletin
CVE-2024-58093NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-58093 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 0a0f9aecf66b98959aab7fb5764b4b3e522f4f5b, 62db339ecc3d58d8fd83a9e4d80061cd943bb6e2, e5cd58f61e9d8024ee11bd78c12c8916891d4077 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 0.24% 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 0a0f9aecf66b98959aab7fb5764b4b3e522f4f5b or 62db339ecc3d58d8fd83a9e4d80061cd943bb6e2 or e5cd58f61e9d8024ee11bd78c12c8916891d4077 or cd4b07507794f7ad1a74e12eca75121d98187e66, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.5 or 5.11 or 5.16 or 6.2, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux666e7f9d60cee23077ea3e6331f6f8a19f7ea03f up to, but not including, 0a0f9aecf66b98959aab7fb5764b4b3e522f4f5b; 7badf4d6f49a358a01ab072bbff88d3ee886c33b up to, but not including, 62db339ecc3d58d8fd83a9e4d80061cd943bb6e2; 9856c0de49052174ab474113f4ba40c02aaee086 up to, but not including, e5cd58f61e9d8024ee11bd78c12c8916891d4077; 7aecdd47910c51707696e8b0e045b9f88bd4230f up to, but not including, cd4b07507794f7ad1a74e12eca75121d98187e66; 456d8aa37d0f56fc9e985e812496e861dcd6f2f2 up to, but not including, 8b930ddc2044e36866c41423e89889e0258695a3; 456d8aa37d0f56fc9e985e812496e861dcd6f2f2 up to, but not including, f556b6ba0ac5f8353287ce6ed761228f0b4fafb7; 456d8aa37d0f56fc9e985e812496e861dcd6f2f2 up to, but not including, ba4cdc14c0d4df00d3e99bff7fe545303db98183; 456d8aa37d0f56fc9e985e812496e861dcd6f2f2 up to, but not including, 4d96930239981f312821a4065db8cc0f8240a173; and 10 more ranges0a0f9aecf66b98959aab7fb5764b4b3e522f4f5b, 62db339ecc3d58d8fd83a9e4d80061cd943bb6e2, e5cd58f61e9d8024ee11bd78c12c8916891d4077, cd4b07507794f7ad1a74e12eca75121d98187e66, 8b930ddc2044e36866c41423e89889e0258695a3, f556b6ba0ac5f8353287ce6ed761228f0b4fafb7
LinuxLinux Kernel5.4.251 up to, but not including, 5.5; 5.10.188 up to, but not including, 5.11; 5.15.121 up to, but not including, 5.16; 6.1.39 up to, but not including, 6.2; 6.3.13 up to, but not including, 6.4; 6.4.4 up to, but not including, 6.155.5, 5.11, 5.16, 6.2, 6.4, 6.15

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.

Official description

In the Linux kernel, the following vulnerability has been resolved: PCI/ASPM: Fix link state exit during switch upstream function removal Before 456d8aa37d0f ("PCI/ASPM: Disable ASPM on MFD function removal to avoid use-after-free"), we would free the ASPM link only after the last function on the bus pertaining to the given link was removed. That was too late. If function 0 is removed before sibling function, link->downstream would point to free'd memory after. After above change, we freed the ASPM parent link state upon any function removal on the bus pertaining to a given link. That is too early. If the link is to a PCIe switch with MFD on the upstream port, then removing functions other than 0 first would free a link which still remains parent_link to the remaining downstream ports. The resulting GPFs are especially frequent during hot-unplug, because pciehp removes devices on the link bus in reverse order. On that switch, function 0 is the virtual P2P bridge to the internal bus. Free exactly when function 0 is removed -- before the parent link is obsolete, but after all subordinate links are gone. [kwilczynski: commit log]

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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