Vulnerability in Shepherd-Agents Shepherd
CVE-2026-108741
Shepherd (shepherd-ai) through 0.3.1 contains a server-side request forgery guard bypass in the citation-checker extra because the public_url guard validates a resolved address but fetch re-resolves the hostname at connect time. Attackers who plant a crafted reference URL in a checked document and control its DNS can rebind it to internal addresses, sending GET requests to internal HTTP(S) services and capturing responses in evidence files.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published .
CVSS v3 metric
CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind03/shepherd-citation-checker-dns-rebinding-ssrf (third-party-advisory)
- github.com/shepherd-agents/shepherd/blob/d34d5ca334871dfcb5a3dc76dd78045829fa4e… (technical-description)
- github.com/shepherd-agents/shepherd/blob/d34d5ca334871dfcb5a3dc76dd78045829fa4e… (technical-description)
- github.com/shepherd-agents/shepherd (product)
- www.vulncheck.com/advisories/shepherd-through-0.3.1-ssrf-via-dns-rebinding-in-c… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-108741?
- CVE-2026-108741 is a low-severity vulnerability in Shepherd-Agents Shepherd, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 3.1/10. Published 2026-10-11.
- How severe is CVE-2026-108741?
- Low severity. CVSS v3 base score is 3.1 out of 10.