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.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/shepherd-agents/shepherd
https://github.com/shepherd-agents/shepherd/blob/d34d5ca334871dfcb5a3dc76dd78045829fa4e56/shepherd/extras/citation-checker/src/shepherd_citation_checker/_engine/fetch.py#L34-L55
https://github.com/shepherd-agents/shepherd/blob/d34d5ca334871dfcb5a3dc76dd78045829fa4e56/shepherd/extras/citation-checker/src/shepherd_citation_checker/_engine/network.py#L9-L17
https://hackmd.io/@haind03/shepherd-citation-checker-dns-rebinding-ssrf
https://www.vulncheck.com/advisories/shepherd-through-0.3.1-ssrf-via-dns-rebinding-in-citation-checker

Configurations

No configuration.

History

11 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 13:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108741

Mitre link : CVE-2026-108741

CVE.ORG link : CVE-2026-108741

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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