CyberSecBulletin
CVE-2022-29581NVD status: Modified

Kernel: Improper Update of Reference Count

Published Updated By the CyberSecBulletin desk

CVE-2022-29581 is a high-severity improper update of reference count vulnerability in Kernel from 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 version 5.18 as the first without the flaw, so updating Kernel to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.93% chance of exploitation within 30 days, higher than 61% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Kernel to 5.18 or a later version.
  2. Update Linux Kernel to 4.14.278 or 4.19.241 or 5.4.191 or 5.10.113, whichever matches your release line, or a later version.
  3. Read the advisory on git.kernel.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxKernelbefore 5.18; 4.145.18
LinuxLinux Kernel4.14 up to, but not including, 4.14.278; 4.15 up to, but not including, 4.19.241; 4.20 up to, but not including, 5.4.191; 5.5 up to, but not including, 5.10.113; 5.11 up to, but not including, 5.15.36; 5.16 up to, but not including, 5.17.54.14.278, 4.19.241, 5.4.191, 5.10.113, 5.15.36, 5.17.5
DebianDebian Linux10.0Not stated
CanonicalUbuntu Linux14.04; 16.04; 18.04; 20.04; 22.04Not stated
NetAppH300s FirmwareNot specified in the recordNot stated
NetAppH500s FirmwareNot specified in the recordNot stated
NetAppH700s FirmwareNot specified in the recordNot stated
NetAppH300e FirmwareNot specified in the recordNot stated
NetAppH500e FirmwareNot specified in the recordNot stated
NetAppH700e FirmwareNot specified in the recordNot stated
NetAppH410s FirmwareNot specified in the recordNot stated
NetAppH410c FirmwareNot specified in the recordNot 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 3.17.8HighCNA (google.com)
CVSS 3.17.8HighNVD
CVSS 2.07.2HighNVD

Official description

Improper Update of Reference Count vulnerability in net/sched of Linux Kernel allows local attacker to cause privilege escalation to root. This issue affects: Linux Kernel versions prior to 5.18; version 4.14 and later versions.

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

The underlying weakness: Improper Update of Reference Count

The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count.

More Improper Update of Reference Count vulnerabilities (CWE-911)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  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 Kernel

All Kernel vulnerabilities

Recent Improper Update of Reference Count vulnerabilities

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