Woodpecker gRPC agent_id metadata can be spoofed- cross-tenant agent impersonation

published 2026-06-18 4 mo ago modified 2026-10-25 14 d ago also GHSA-g7mm-9vx7-jm7h , GO-2026-5976 , EUVD-2026-37897

cvss: 7.1; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits: 0; none known

Woodpecker is a CI/CD engine. Starting in version 3.0.0 and prior to version 3.14.1, a vulnerability in Woodpecker CI's gRPC layer allowed any authenticated agent to impersonate any other agent on the same server by injecting a forged `agent_id` value into outgoing gRPC metadata. The server correctly verified the JWT token but then discarded the verified agent identity in favor of the client-supplied value. Version 3.14.1 patches the issue. As a workaround, disable org agents (`WOODPECKER_DISABLE_USER_AGENT_REGISTRATION=true`) and delete existing ones.

Patch / fix

fixed in 1 distros 1 links 2

go go.woodpecker-ci.org/woodpecker/v3 3.14.1

govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1

opensuse advisories openSUSE-SU-2026:21483-1

github.com/woodpecker-ci/woodpecker#6567 pull request
github.com/woodpecker-ci/woodpecker#6569 pull request

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 4 mo ago (2026-06-18)

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/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

Affected packages

ecosystem	package	affected	fixed in
go	go.woodpecker-ci.org/woodpecker/v3	>=3.0.0, <3.14.1	3.14.1
go	go.woodpecker-ci.org/woodpecker	all versions	no fix listed
go	go.woodpecker-ci.org/woodpecker/v2	all versions	no fix listed

Affected products

woodpecker-ci woodpecker

Classification

Weakness

CWE-290 Authentication Bypass by Spoofing
CWE-639 Authorization Bypass Through User-Controlled Key

References

Sources

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