CVE-2026-72691
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
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.
Risk Assessment
An attacker can gain unauthorized access to stored files, potentially leading to exposure of sensitive data.
Recommendation
Update opensignserver to the latest version and fix the authentication logic in the getsignedurl function. Ensure identity verification is performed regardless of input parameters.
Other vulnerabilities in OpenSignLabs opensignserver
See all- CVE-2026-72692High
A missing authorization vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to irreversibly decline any in-flight document and forge the decline attribution to an arbitrary user via the declinedoc Parse cloud function. The function writes IsDeclined, DeclineReason, and a caller-supplied DeclineBy pointer without verifying the caller's identity, enabling workflow termination and evidentiary record falsification.
- CVE-2026-72689High
A broken object-level authorization vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to read complete contract records via the getDocument Parse cloud function. The function fetches documents using useMasterKey, bypassing the object ACL, and returns full records including sender and signer PII and a pre-signed document download URL whenever the document's IsEnableOTP flag is unset.
- CVE-2026-72688High
A missing authentication vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to read arbitrary stored documents via the fileupload Parse cloud function. The function mints MASTER_KEY-signed file access tokens for any caller-supplied URL without performing any session check, defeating the only access control protecting stored contract files.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS