CyberSecBulletin
CVE-2026-5816NVD status: Analyzed

GitLab: Improper Resolution of Path Equivalence

Published Updated By the CyberSecBulletin desk

CVE-2026-5816 is a high-severity improper resolution of path equivalence vulnerability in GitLab, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 18.10.4, 18.11.1 as the first without the flaw, so updating GitLab to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.41% 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 GitLab to 18.10.4 or 18.11.1, whichever matches your release line, or a later version.
  2. Read the advisory on about.gitlab.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. 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
GitLabGitLab18.10 up to, but not including, 18.10.4; 18.11 up to, but not including, 18.11.118.10.4, 18.11.1

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
NoneNo account or login is needed.
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:N/UI:R/S:U/C:H/I:H/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.0HighCNA (gitlab.com)
CVSS 3.18.1HighNVD

Official description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.10 before 18.10.4 and 18.11 before 18.11.1 that could have allowed an unauthenticated user to execute arbitrary JavaScript in a user's browser session due to improper path validation under certain conditions.

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

The underlying weakness: Improper Resolution of Path Equivalence

The product is vulnerable to file system contents disclosure through path equivalence. Path equivalence involves the use of special characters in file and directory names. The associated manipulations are intended to generate multiple names for the same object.

How developers prevent this class of flaw

  • Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.

More Improper Resolution of Path Equivalence vulnerabilities (CWE-41)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, 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 Resolution of Path Equivalence vulnerabilities

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