Medium
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab
Type: advisorySources: OSV
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.7 before 18.8.7, 18.9 before 18.9.3, and 18.10 before 18.10.1 that could have allowed an authenticated user to execute arbitrary JavaScript in a user's browser due to improper sanitization of entity-encoded content in Mermaid diagrams.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-2973
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 15:19 UTC · Revision 1
Source evidence
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab
core-osv · Original sourcePublished 25 Mar 2026, 16:34 UTC
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.7 before 18.8.7, 18.9 before 18.9.3, and 18.10 before 18.10.1 that could have allowed an authenticated user to execute arbitrary JavaScript in a user's browser due to improper sanitization of entity-encoded content in Mermaid diagrams.
osv:CVE-2026-2973
Complete source record
{
"id": "ed7bac7521f26642180ebd5db43b456d79e481d9f9692c60d06a4d2a7b42f00e",
"url": "https://osv.dev/vulnerability/CVE-2026-2973",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab",
"summary": "GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.7 before 18.8.7, 18.9 before 18.9.3, and 18.10 before 18.10.1 that could have allowed an authenticated user to execute arbitrary JavaScript in a user's browser due to improper sanitization of entity-encoded content in Mermaid diagrams.",
"evidence": "osv:CVE-2026-2973",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-2973",
"aliases": [
"BIT-gitlab-2026-2973",
"CVE-2026-2973"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://gitlab.com/gitlab-org/gitlab",
"type": "GIT",
"events": [
{
"introduced": "1fd574ee5710155adf5307fba45132264dcb64a1"
},
{
"fixed": "bbb3a4b03698954b5a8efb0de7bafc061c303ed6"
},
{
"introduced": "20fe49b575fedd2b8cadc2c0640178879854aeb3"
},
{
"fixed": "d0161a9f097f49a9d33a4d8fe1d5a827ee777d67"
},
{
"introduced": "57c08314af5bc8f317b1967330f92ed029e2c628"
},
{
"last_affected": "57c08314af5bc8f317b1967330f92ed029e2c628"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*",
"range": [
{
"introduced": "17.7.0"
},
{
"fixed": "18.8.7"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*",
"range": [
{
"introduced": "17.7.0"
},
{
"fixed": "18.8.7"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*",
"range": [
{
"introduced": "18.9.0"
},
{
"fixed": "18.9.3"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*",
"range": [
{
"introduced": "18.9.0"
},
{
"fixed": "18.9.3"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:gitlab:gitlab:18.10.0:*:*:*:community:*:*:*",
"range": [
{
"introduced": "18.10.0"
},
{
"last_affected": "18.10.0"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:gitlab:gitlab:18.10.0:*:*:*:enterprise:*:*:*",
"range": [
{
"introduced": "18.10.0"
},
{
"last_affected": "18.10.0"
}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
"18.10.0",
"v18.9.0-ee",
"v18.10.0-ee"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-2973.json"
}
}
],
"modified": "2026-10-30T10:30:43.329015136Z",
"provider": "osv",
"references": [
"https://about.gitlab.com/releases/2026/03/25/patch-release-gitlab-18-10-1-released/",
"https://gitlab.com/gitlab-org/gitlab/-/work_items/591049",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2973.json",
"https://nvd.nist.gov/vuln/detail/CVE-2026-2973",
"https://hackerone.com/reports/3566802"
],
"provider_metadata": {
"cwe_ids": [
"CWE-79"
],
"cna_assigner": "GitLab",
"unresolved_ranges": [
{
"extracted_events": [
{
"range": [
{
"introduced": "17.7"
},
{
"fixed": "18.8.7"
},
{
"introduced": "18.9"
},
{
"fixed": "18.9.3"
},
{
"introduced": "18.10"
},
{
"fixed": "18.10.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
}
]
},
{
"extracted_events": [
{
"range": [
{
"introduced": "17.7"
},
{
"fixed": "18.8.7"
},
{
"introduced": "18.9"
},
{
"fixed": "18.9.3"
},
{
"introduced": "18.10"
},
{
"fixed": "18.10.1"
}
],
"source": "DESCRIPTION"
}
]
}
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2973.json"
}
},
"related_cves": [
{
"value": "CVE-2026-2973",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 496759,
"published_at": "2026-03-25T16:34:03.852+00:00"
}