Documenso Google OAuth Login handle-oauth-callback-url.ts improper authentication

published 2026-06-29 4 mo ago modified 2026-06-29 4 mo ago also EUVD-2026-40043

cvss: 5.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits: 0; none known

A vulnerability was detected in Documenso up to 2.11.0. Affected by this vulnerability is an unknown functionality of the file packages/auth/server/lib/utils/handle-oauth-callback-url.ts of the component Google OAuth Login. The manipulation results in improper authentication. It is possible to launch the attack remotely. This attack is characterized by high complexity. The exploitation appears to be difficult. The exploit is now public and may be used. The pull request to fix this issue awaits acceptance.

Patch / fix

links 1

github.com/documenso/documenso#2837 pull request

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 4 mo ago (2026-06-29)

Exploit prediction

0.59% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/documenso/documenso/issues/2758 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.3	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	3.0	5.6	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	2.0	5.1	AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA	4.0	2.9	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
CNA	2.0	5.1	AV:N/AC:H/Au:N/C:P/I:P/A:P

Affected products

n/a Documenso

Classification

Weakness

CWE-287 Improper Authentication

References

github.com /documenso/documenso/pull/2837
issue-tracking, patch
github.com /documenso/documenso/issues/2758
exploit, issue-tracking
vuldb.com /vuln/374551
vdb-entry
vuldb.com /vuln/374551/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-13543
third-party-advisory
vuldb.com /submit/842579
third-party-advisory
github.com /documenso/documenso/
product

Sources

CVE List CVE-2026-13543
NVD CVE-2026-13543

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary