CVE-2021-39885Public exploitNetwork attack vector

Stored XSS via unsanitized approval rule names

Published Oct 4, 2021 · Updated Aug 4, 2024

Stored XSS in GitLab EE 13.7 through 14.1.6, 14.2.0 through 14.2.4, and 14.3.0 allows remote authenticated users to execute JavaScript. The merge request creation page renders an approval rule name beneath reviewer details without sanitizing its HTML, allowing stored markup to bypass the page content security policy. The attacker needs approval-rule access, and a victim must open the Reviewers dropdown; the script then acts in the victim session and can read data or create access tokens.

CVSS severity8.7
High
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in GitLab EE 13.7 through 14.1.6, 14.2.0 through 14.2.4, and 14.3.0 allows remote authenticated users to execute JavaScript. The merge request creation page renders an approval rule name beneath reviewer details without sanitizing its HTML, allowing stored markup to bypass the page content security policy. The attacker needs approval-rule access, and a victim must open the Reviewers dropdown; the script then acts in the victim session and can read data or create access tokens.

The record

CVE
CVE-2021-39885
Published
Oct 4, 2021
Updated
Aug 4, 2024
Vendor
GitLab
Product
GitLab
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>=13.7, <14.1.7
  2. Affected versionversion=>=14.2, <14.2.5
  3. Affected versionversion=>=14.3, <14.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

GitLab · GitLabversion=>=13.7, <14.1.7; version=>=14.2, <14.2.5; version=>=14.3, <14.3.1

Published CVSS scores

8.7GitLabCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
5.4NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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