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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction Passive

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
shepherd-agents Shepherd unaffected
Version Status Constraints
0 affected ≤ 0.3.1

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

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

Sun, 11 Oct 2026 12:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Shepherd through 0.3.1 SSRF via DNS Rebinding in Citation Checker
Weaknesses CWE-367
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 2.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-10-11T12:19:45.494Z

Reserved: 2026-10-11T01:52:55.363Z

Link: CVE-2026-108741

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-11T13:17:18.673

Modified: 2026-10-11T13:17:18.673

Link: CVE-2026-108741

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses