CyberSecBulletin
CVE-2022-4331NVD status: Modified

GitLab: Improper Access Control

Published Updated By the CyberSecBulletin desk

CVE-2022-4331 is a high-severity improper access control vulnerability in GitLab, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected GitLab versions: >=15.1, <15.7.8; >=15.8, <15.8.4; >=15.9, <15.9.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of GitLab you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on gitlab.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
GitLabGitLab>=15.1, <15.7.8; >=15.8, <15.8.4; >=15.9, <15.9.2Not 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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
RequiredA user must take an action such as opening a file or link.
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
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.7MediumCNA (gitlab.com)
CVSS 3.17.3HighNVD

Official description

An issue has been discovered in GitLab EE affecting all versions starting from 15.1 before 15.7.8, all versions starting from 15.8 before 15.8.4, all versions starting from 15.9 before 15.9.2. If a group with SAML SSO enabled is transferred to a new namespace as a child group, it's possible previously removed malicious maintainer or owner of the child group can still gain access to the group via SSO or a SCIM token to perform actions on the group.

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

The underlying weakness: Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Improper Access Control vulnerabilities (CWE-284)

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

Other references

Other vulnerabilities in GitLab

All GitLab vulnerabilities

Recent Improper Access Control vulnerabilities

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