CyberSecBulletin
CVE-2024-47747NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-47747 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.0 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 25d559ed2beec9b34045886100dac46d1ad92eba, b5a84b6c772564c8359a9a0fbaeb2a2944aa1ee9, 338a0582b28e69460df03af50e938b86b4206353 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 0.23% 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 25d559ed2beec9b34045886100dac46d1ad92eba or b5a84b6c772564c8359a9a0fbaeb2a2944aa1ee9 or 338a0582b28e69460df03af50e938b86b4206353 or 822c7bb1f6f8b0331e8d1927151faf8db3b33afd, 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 RUGGEDCOM RST2428P to V3.2 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 25d559ed2beec9b34045886100dac46d1ad92eba; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, b5a84b6c772564c8359a9a0fbaeb2a2944aa1ee9; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 338a0582b28e69460df03af50e938b86b4206353; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 822c7bb1f6f8b0331e8d1927151faf8db3b33afd; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 1c57d61a43293252ad732007c7070fdb112545fd; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, d2abc379071881798d20e2ac1d332ad855ae22f3; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 516dbc6d16637430808c39568cbb6b841d32b55b; 6fd9c53f71862a4797b7ed8a5de80e2c64829f56 up to, but not including, 77a77331cef0a219b8dd91361435eeef04cb741c; and 2 more ranges25d559ed2beec9b34045886100dac46d1ad92eba, b5a84b6c772564c8359a9a0fbaeb2a2944aa1ee9, 338a0582b28e69460df03af50e938b86b4206353, 822c7bb1f6f8b0331e8d1927151faf8db3b33afd, 1c57d61a43293252ad732007c7070fdb112545fd, d2abc379071881798d20e2ac1d332ad855ae22f3
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1.1V1.1.1
SiemensRUGGEDCOM RST2428Pbefore V3.2V3.2
SiemensSCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 familybefore V3.2V3.2
SiemensSCALANCE XCM-/XRM-/XCH-/XRH-300 familybefore V3.2V3.2
LinuxLinux Kernel4.15 up to, but not including, 5.10.227; 5.11 up to, but not including, 5.15.168; 5.16 up to, but not including, 6.1.113; 6.2 up to, but not including, 6.6.54; 6.7 up to, but not including, 6.10.13; 6.11 up to, but not including, 6.11.25.10.227, 5.15.168, 6.1.113, 6.6.54, 6.10.13, 6.11.2

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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
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:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA
CVSS 3.17.0HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: net: seeq: Fix use after free vulnerability in ether3 Driver Due to Race Condition In the ether3_probe function, a timer is initialized with a callback function ether3_ledoff, bound to &prev(dev)->timer. Once the timer is started, there is a risk of a race condition if the module or device is removed, triggering the ether3_remove function to perform cleanup. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | ether3_ledoff ether3_remove | free_netdev(dev); | put_devic | kfree(dev); | | ether3_outw(priv(dev)->regs.config2 |= CFG2_CTRLO, REG_CONFIG2); | // use dev Fix it by ensuring that the timer is canceled before proceeding with the cleanup in ether3_remove.

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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