Security readout for executives and security teams
Plain-English summary
GitLab fixed a high-severity issue where an authenticated user could use HTML injection in test case titles to add unauthorized email addresses to another user’s account under certain conditions. This can affect account integrity and confidentiality because email addresses can influence notifications, identity, and account workflows.
Executive priority
Treat this as a prompt patching priority for GitLab environments, especially where many users can authenticate. The issue can affect account trust and sensitive communications, but current sources do not show active exploitation.
Technical view
CVE-2026-0595 is CWE-79 cross-site scripting / improper input neutralization in GitLab CE/EE. Affected versions are 13.9 before 18.6.6, 18.7 before 18.7.4, and 18.8 before 18.8.4. CVSS 3.1 is 7.3, with network access, low complexity, low privileges, and required user interaction.
Likely exposure
Self-managed GitLab CE/EE instances in the affected version ranges are the primary exposure. Exploitation requires an authenticated user and victim interaction. The source bundle does not establish exposure for any other products or services.
Exploitation context
The CVE is not listed as KEV, and the provided sources do not state active exploitation. Public references include GitLab’s release notice and restricted issue/bug bounty pages. The known impact is unauthorized email address addition through HTML injection in test case titles.
Researcher notes
Key technical details are limited because the GitLab issue and HackerOne report are marked permissions-required in the source bundle. Avoid assuming exploit mechanics beyond the CVE description: authenticated user, HTML injection in test case titles, victim interaction, and unauthorized email additions.
Mitigation direction
- Upgrade GitLab CE/EE to 18.6.6, 18.7.4, 18.8.4, or a later fixed version.
- Prioritize instances with broad user access or untrusted project collaborators.
- Check GitLab’s release advisory for any updated remediation guidance.
- If immediate upgrade is delayed, reduce access for untrusted authenticated users where feasible.
Validation and detection
- Inventory GitLab CE/EE versions across all self-managed instances.
- Confirm no instance runs 13.9 through vulnerable 18.8 patch levels.
- Review account email changes for unexpected additions after potential exposure windows.
- Monitor GitLab advisories for clarifications on affected configurations and detection guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-0595 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N2.15.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.3HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- GitLab Issue #584975CVE reference · issue-tracking, permissions-required
- HackerOne Bug Bounty Report #3486862CVE reference · technical-description, exploit
- https://about.gitlab.com/releases/2026/02/10/patch-release-gitlab-18-8-4-released/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.