CyberSecBulletin
CVE-2022-41973NVD status: Modified

Multipath-tools: Improper Link Resolution Before File Access

Published Updated By the CyberSecBulletin desk

CVE-2022-41973 is a high-severity improper link resolution before file access vulnerability in Multipath-tools from Opensvc, 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 0.9.2 as the first without the flaw, so updating Multipath-tools to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.68% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Multipath-tools to 0.9.2 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
OpensvcMultipath-tools0.7.7 up to, but not including, 0.9.20.9.2
Fedora ProjectFedora36Not stated
DebianDebian Linux10.0Not stated

Version data comes from NVD's product matching. 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

multipath-tools 0.7.7 through 0.9.x before 0.9.2 allows local users to obtain root access, as exploited in conjunction with CVE-2022-41974. Local users able to access /dev/shm can change symlinks in multipathd due to incorrect symlink handling, which could lead to controlled file writes outside of the /dev/shm directory. This could be used indirectly for local privilege escalation to root.

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

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other vulnerabilities in Multipath-tools

All Multipath-tools vulnerabilities

Recent Improper Link Resolution Before File Access vulnerabilities

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