CVE-2021-22242

published 2021-08-25

CVE-2021-22242: Insufficient input sanitization in Mermaid markdown in GitLab CE/EE version 11.4 and up allows an attacker to exploit a stored cross-site scripting…

Priority P3 43 medium 5.4 CVSS 3.1

AV N AC L PR L UI R S C C L I L A N

Insufficient input sanitization in Mermaid markdown in GitLab CE/EE version 11.4 and up allows an attacker to exploit a stored cross-site scripting vulnerability via a specially-crafted markdown

Affected

9 ranges

Vendor	Product	Version range	Fixed in
debian	gitlab	< gitlab 15.10.8+ds1-2 (sid)	gitlab 15.10.8+ds1-2 (sid)
gitlab	gitlab	—	—
gitlab	gitlab	—	—
gitlab	gitlab	—	—
gitlab	gitlab	—	—
gitlab	gitlab	>= 11.4.0 < 13.12.9	13.12.9
gitlab	gitlab	>= 14.0.0 < 14.0.7	14.0.7
gitlab	gitlab	>= 14.1.0 < 14.1.2	14.1.2
gitlab	gitlab_ce	—	—

Detection & IOCs extracted from sources · hover to see the quote

• → Stored XSS via specially-crafted Mermaid markdown input in GitLab CE/EE; monitor for unsanitized Mermaid diagram blocks in GitLab markdown fields that contain JavaScript payloads or event handlers ↗

• · Vulnerability affects GitLab CE/EE version 11.4 and up; Debian sid resolved the issue in version 15.10.8+ds1-2 ↗

CVSS provenance

nvd v3.1 5.4 MEDIUM CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

nvd v2.0 3.5 LOW AV:N/AC:M/Au:S/C:N/I:P/A:N

osv 5.4 MEDIUM

vendor_debian 8.7 HIGH

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CWE-79