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Full vulnerability report · 2026
CVE-2026-1338High confidence

Authorization Bypass Through User-Controlled Key in GitLab

GitLab · GitLab

4.3MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.19% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs GitLab GitLab and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-30221

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.10 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3 that could have allowed an authenticated user with developer-role permissions to delete protected container registry tags due to improper authorization checks.

What

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.10 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3 that could have allowed an authenticated user with developer-role permissions to delete protected container registry tags due to improper authorization checks.

Why

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.10 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3 that could have allowed an authenticated user with developer-role permissions to delete protected container registry tags due to improper authorization checks.

Why

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Authorization Bypass Through User-Controlled Key → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-639 ↗

CWE-639: Authorization Bypass Through User-Controlled Key. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkCWE-639
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2026-1523GitLab: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in GitLab ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, und um Sicherheitsvorkehrungen zu umgehen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260520Security Bulletin 20 May 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 20 May 2026, published on 20 May 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0593Multiples vulnérabilités dans GitLab

correctifs (cf. section Documentation). Documentation Bulletin de sécurité GitLab du 13 mai 2026 https://docs.gitlab.com/releases/patches/patch-release-gitlab-18-11-3-released/ Référence CVE CVE-2025-12669 https://www.cve.org/CVERecord?id=CVE-2025-12669 Référence CVE CVE-2025-13874 https://www.cve.org/CVERecord?id=CVE-2025-13874 Référence CVE CVE-2025-14869 https://www.cve.org/CVERecord?id=CVE-2025-14869 Référence CVE CVE-2025-14870 https://www.cve.org/CVERecord?id=CVE-2025-14870 Référence CVE CVE-2026-1184 https://www.cve.org/CVERecord?id=CVE-2026-1184 Référence CVE CVE-2026-1322 https://www.cve.org/CVERecord?id=CVE-2026-1322 Référence CVE CVE-2026-1338 https://www.cve.org/CVERecord?id=CVE-2026-1338 Référence CVE CVE-2026-1659 https://www.cve.org/CVERecord?id=CVE-2026-1659 Référence CVE CVE-2026-2900 https://www.cve.org/CVERecord?id=CVE-2026-2900 Référence CVE CVE-2026-3073 https://www.cve.org/CVERecord?id=CVE-2026-3073 Référence CVE CVE-2026-3074 https://www.cve.org/CVERecord?id=CVE-2026-3074 Référence CVE CVE-2026-3160 https://www.cve.org/CVERecord?id=CVE-2026-3160 Référence CVE CVE-2026-3607 https://www.cve.org/CVERecord?id=CVE-2026-3607 Référence CVE CVE-2026-4524 https://www.cve.org/CVERecord?id=CVE-2026-4524 Référence CVE CVE-2026-4527 https://www.cve.org/CVERecord?id=CVE-2026-4527 Ré

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-016008GitLab.orgのGitLabにおけるユーザ制御の鍵による認証回避に関する脆弱性

GitLabは、認証された開発者ロールのユーザーが不適切な認可チェックにより保護されたコンテナレジストリのタグを削除できてしまう可能性のある問題を修正しました。この問題はGitLab CE/EEのバージョン17.10から18.9.7未満、18.10から18.10.6未満、18.11から18.11.3未満のすべてのバージョンに影響しています。

Official advisory ↗
NCSC-NL · Dutch · NCSC-2026-0161Kwetsbaarheden verholpen in GitLab door GitLab Inc.

GitLab addressed a security flaw in versions prior to 18.9.7, 18.10.6, and 18.11.3 where authenticated users with developer permissions could delete protected container registry tags due to improper authorization checks.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
GitLab: 17.10 < 18.9.7, 18.10 < 18.10.6, 18.11 < 18.11.3
Fixed
Upgrade to versions 18.9.7, 18.10.6, 18.11.3 or above.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 14 May 2026 · Last source change 14 May 2026, 13:05 UTC · CWE-639 · Authorization Bypass Through User-Controlled Key

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-30221
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-1338 · cve.blacktree.nl