What happened
Microsoft SharePoint contains a weak authentication vulnerability which allows an unauthorized attacker to bypass a security feature over a network.
Affected versions
SharePoint: See original advisory Fixed: See vendor advisory.
Why it matters
This source correlation may provide earlier visibility while structured CVE metadata is still being updated.
Detection & mitigation
- Review the original advisory and validate affected versions.
- Apply vendor-provided updates or mitigations when available.
Public PoC references
RepositoryAuthorFirst seenReference
CVE-Intel · zenzue/CVE-2026-55040ExploitPython★ 0⑂ 0Code indexedUpdated 26 Aug 2026zenzue2026-08-26CandidateCVE-Intel · sfewer-r7/CVE-2026-55040Microsoft SharePoint JWT Authentication Bypass (CVE-2026-55040)BypassPython★ 56⑂ 13Code indexedUpdated 22 Aug 2026sfewer-r72026-08-06CandidateCVE-Intel · l0ggg/CVE-2026-55040Exploit code for CVE-2026-55040, it can create auth header for any validate account.ExploitPython★ 3⑂ 1Code indexedUpdated 20 Aug 2026l0ggg2026-07-28CandidateSource timeline
Discovered through CISA Known Exploited VulnerabilitiesView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Added to CISA Known Exploited Vulnerabilities catalogView source ↗
Record history
Record created from the first normalized source observation.
Metadata and source references refreshed.