CVE-2026-82757

Server-Side Request Forgery (SSRF) vulnerability in ash-project ash_authentication_oauth2_server allows an attacker who controls a client metadata URL and its DNS to make the server connect to internal or loopback addresses. public_ip?/1 in AshAuthentication.Oauth2Server.CIMD.ReqFetcher enforces the outbound policy for CIMD metadata fetches. It classified several address forms as publicly routable that are not: IPv4-compatible ::/96 (for example ::127.0.0.1), SIIT IPv4-translated ::ffff:0:0:0/96, and deprecated site-local fec0::/10. A returned AAAA record in one of these ranges passed the policy, so a fetch pinned to that address reached space the policy was meant to block. This issue affects ash_authentication_oauth2_server: from 0.3.0 before 0.3.1.

CVSS

No CVSS.

References

Link	Resource
https://cna.erlef.org/cves/CVE-2026-82757.html
https://github.com/ash-project/ash_authentication_oauth2_server/commit/268b591261a3473ab9b87272963e4dd2fd99d972
https://github.com/ash-project/ash_authentication_oauth2_server/security/advisories/GHSA-wprp-8gvj-p6cv
https://osv.dev/vulnerability/EEF-CVE-2026-82757

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 23:16

Updated : 2026-09-08 15:18

NVD link : CVE-2026-82757

Mitre link : CVE-2026-82757

CVE.ORG link : CVE-2026-82757

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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It classified several address forms as publicly routable that are not: IPv4-compatible ::/96 (for example ::127.0.0.1), SIIT IPv4-translated ::ffff:0:0:0/96, and deprecated site-local fec0::/10. A returned AAAA record in one of these ranges passed the policy, so a fetch pinned to that address reached space the policy was meant to block.\n\nThis issue affects ash_authentication_oauth2_server: from 0.3.0 before 0.3.1."}], "lastModified": "2026-09-08T15:18:50.823", "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}