CVE-2023-5356: gitlab Auth Bypass (CVSS 7.3)

Description

Incorrect authorization checks in GitLab CE/EE from all versions starting from 8.13 before 16.5.6, all versions starting from 16.6 before 16.6.4, all versions starting from 16.7 before 16.7.2, allows a user to abuse slack/mattermost integrations to execute slash commands as another user.

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CVSS v3.1 Score

7.3

HIGH

CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N

Weakness Type (CWE)

CWE-863 Incorrect Authorization

Affected Products

Vendor	Product	Versions
gitlab	gitlab	8.13.0 — 16.5.6
gitlab	gitlab	8.13.0 — 16.5.6
gitlab	gitlab	16.6.0 — 16.6.4
gitlab	gitlab	16.6.0 — 16.6.4
gitlab	gitlab	All
gitlab	gitlab	All
gitlab	gitlab	All
gitlab	gitlab	All

References

Other References

https://gitlab.com/gitlab-org/gitlab/-/issues/427154 https://hackerone.com/reports/2188868 https://gitlab.com/gitlab-org/gitlab/-/issues/427154 https://hackerone.com/reports/2188868

Frequently Asked Questions

What is CVE-2023-5356? +

Incorrect authorization checks in GitLab CE/EE from all versions starting from 8.13 before 16.5.6, all versions starting from 16.6 before 16.6.4, all versions starting from 16.7 before 16.7.2, allows a user to abuse slack/mattermost integrations to execute slash commands as another user. It has a CVSS v3.1 base score of 7.3 (HIGH).

How severe is CVE-2023-5356? +

CVE-2023-5356 has a CVSS v3.1 score of 7.3 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-5356? +

CVE-2023-5356 affects products from gitlab, specifically: gitlab. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-5356? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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