CVE-2026-72691 OpenSignLabs opensignserver - Authentication Bypass
Unauthenticated attackers can bypass authentication in OpenSignLabs opensignserver to mint signed access tokens for arbitrary files, enabling unauthorized data access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-72691?
CVE-2026-72691 is a high-severity authentication bypass vulnerability in OpenSignLabs opensignserver, published on 10 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An authentication bypass vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to mint MASTER_KEY-signed file access tokens for arbitrary stored files via the getsignedurl Parse cloud function. The function skips its isAuthenticated check whenever any docId parameter is supplied, even one corresponding to no real document, allowing the authentication gate to be bypassed by supplying an arbitrary string as docId.
Weakness: CWE-288
Which versions are affected by CVE-2026-72691?
How do I fix CVE-2026-72691?
No fix has been published for CVE-2026-72691 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-72691 being exploited?
There is no known exploitation of CVE-2026-72691 in the wild and no public exploit code.
Sources
Also known as GHSA-9g58-36q9-g7mq.