CyberSecBulletin
CVE-2022-2588NVD status: Modified

linux: Double Free

Published Updated By the CyberSecBulletin desk

CVE-2022-2588 is a high-severity double free vulnerability in linux from The Linux Kernel Organization, 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 version 6.0~rc1 as the first without the flaw, so updating linux to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 5.87% chance of exploitation within 30 days, which is in the top 6.67% of all scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update linux to 6.0~rc1 or a later version.
  2. Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1 or a later version.
  3. Update Linux Kernel to 4.9.326 or 4.14.291 or 4.19.256 or 5.4.211, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
The Linux Kernel Organizationlinuxbefore 6.0~rc16.0~rc1
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1V1.1
LinuxLinux Kernelbefore 4.9.326; 4.10 up to, but not including, 4.14.291; 4.15 up to, but not including, 4.19.256; 4.20 up to, but not including, 5.4.211; 5.5 up to, but not including, 5.10.137; 5.11 up to, but not including, 5.15.61; 5.16 up to, but not including, 5.18.18; 5.19 up to, but not including, 5.19.24.9.326, 4.14.291, 4.19.256, 5.4.211, 5.10.137, 5.15.61
CanonicalUbuntu Linux14.04; 16.04; 18.04; 20.04; 22.04Not 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 3.15.3MediumCNA (ubuntu.com)
CVSS 3.17.8HighNVD

Official description

It was discovered that the cls_route filter implementation in the Linux kernel would not remove an old filter from the hashtable before freeing it if its handle had the value 0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Double Free

The product calls free() twice on the same memory address.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
  • Use a static analysis tool to find double free instances.

More Double Free vulnerabilities (CWE-415)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Technical write-ups (may include proof of concept)

Other vulnerabilities in linux

All linux vulnerabilities

Recent Double Free vulnerabilities

Spotted an error? Tell us.