Cyber Resilience

CVE-2023-5933

XSS in Gitlab 13.7.0 – 16.6.6

XSS
Published
26 January 2024
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 6.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
EPSS Score 0.0068 49th percentile
Risk Priority 57 floored blend · peak EPSS

Summary

CVE-2023-5933 is a medium-severity Basic XSS (CWE-80) vulnerability in Gitlab Gitlab. Its CVSS base score is 6.4 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 49th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

An issue has been discovered in GitLab CE/EE involving improper input sanitization of user names that permits arbitrary API PUT requests. The vulnerability affects all versions after 13.7 before 16.6.6, 16.7 prior to 16.7.4, and 16.8 prior to 16.8.1. It is tracked under CWE-80 and CWE-79 with a CVSS 3.1 score of 6.4 reflecting network attack vector, high attack complexity, low privileges required, and user interaction.

An authenticated attacker with low privileges can supply a crafted user name that bypasses sanitization, enabling them to issue unauthorized API PUT requests. Successful exploitation can result in high impact to confidentiality and integrity on affected instances while availability remains unaffected.

GitLab security advisories for the 16.8.1 release and corresponding issue trackers recommend immediate upgrade to the fixed versions 16.6.6, 16.7.4, or 16.8.1 depending on the release line in use.

EPSS remains at 0.1036 with no material increase from its initial value after disclosure.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

An issue has been discovered in GitLab CE/EE affecting all versions after 13.7 before 16.6.6, 16.7 prior to 16.7.4, and 16.8 prior to 16.8.1. Improper input sanitization of user name allows arbitrary API PUT requests.

CWE(s)
CWE-80CWE-79

Related Threats

MITRE ATT&CK Enterprise Techniques

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-2995Same product: Gitlab Gitlab
CVE-2023-2442Same product: Gitlab Gitlab
CVE-2023-2164Same product: Gitlab Gitlab
CVE-2023-1836Same product: Gitlab Gitlab
CVE-2022-1190Same product: Gitlab Gitlab
CVE-2023-2015Same product: Gitlab Gitlab
CVE-2020-13340Same product: Gitlab Gitlab
CVE-2022-1175Same product: Gitlab Gitlab
CVE-2023-6033Same product: Gitlab Gitlab
CVE-2022-2230Same product: Gitlab Gitlab

Affected Assets

gitlab
gitlab
16.8.0 · 13.7.0 — 16.6.6 · 13.7.0 — 16.6.6 · 16.7.0 — 16.7.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.1.2
  • V1.3.2
  • V1.2.1
  • V1.3.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover missing or incorrect neutralization of script tags through targeted XSS test cases.

SI-10 Information Input Validation good match

Input validation explicitly requires checking and neutralizing untrusted web inputs containing script-related characters before they reach a downstream renderer.

SI-15 Information Output Filtering good match

Output filtering can catch or sanitize unneutralized script content before it is served to users.

SA-8 Security and Privacy Engineering Principles partial match

Secure engineering principles include mandatory output encoding and neutralization of HTML metacharacters to stop injection at the source.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require output encoding and input validation that prevent basic XSS.

PR.PS-02 partial match
prevents

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches unneutralized script tags before release.

A.5.6 Contact with special interest groups partial match
prevents

Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.

A.5.7 Threat intelligence partial match
prevents

Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and output encoding that directly prevent basic XSS.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for neutralization of script-related HTML tags.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper escaping of <, >, & to block XSS.

References