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TI-2026-01913 Aliases CVE-2026-2266GHSA-vg33-x66f-82h4

Cross-site scripting in GitHub Enterprise Server

Priority LOW 34CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Passive
Attack complexity
Low
Attack requirements
Present
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

An improper neutralization of input vulnerability was identified in GitHub Enterprise Server that allowed DOM-based cross-site scripting via task list content. The task list content extraction logic did not properly re-encode browser-decoded text nodes before rendering, allowing user-supplied HTML to be injected into the page. An authenticated attacker could craft malicious task list items in issues or pull requests to execute arbitrary scripts in the context of another user's browser session. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.18.6 and 3.19.3. This vulnerability was reported via the GitHub Bug Bounty program.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00211 11th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
GitHubEnterprise Server3.18.0 – 3.18.5; 3.19.0 – 3.19.2—No fix listedCNA
  • Enterprise Server VendorGitHub Affected 3.18.0 – 3.18.5; 3.19.0 – 3.19.2 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*before 3.18.6; 3.19.0 to before 3.19.3VulnerableGitHub
  • cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* Versions before 3.18.6; 3.19.0 to before 3.19.3 Vulnerable ·GitHub

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-2266
  2. 2026-10-03 Alias added: GHSA-vg33-x66f-82h4

References

Other 2

  • TI-2024-04632 An authentication bypass vulnerability was present in the GitHub Enterprise Server (GHES)… CVSS 4.0CRITICAL 10.0
  • TI-2024-00181 Unsafe Reflection in Github Enterprise Server leading to Command Injection CVSS 3.1CRITICAL 9.8
  • TI-2024-00466 Privilege Escalation by Code Injection in the Management Console in GitHub Enterprise Server CVSS 3.1HIGH 8.8
  • TI-2026-03340 Remote code execution via git push option injection in GitHub Enterprise Server CVSS 4.0HIGH 8.7
  • TI-2024-08804 Improper signature verification in GitHub Enterprise Server CVSS 4.0CRITICAL 9.5
  • TI-2026-08177 Server-side request forgery in GitHub Enterprise Server CVSS 4.0CRITICAL 9.2
See all 125 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences