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.
Metrics
Affected Vendors & Products
No advisories yet.
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Tue, 08 Sep 2026 15:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
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Mon, 07 Sep 2026 22:45:00 +0000
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| Description | 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. | |
| Title | ash_authentication_oauth2_server CIMD fetcher classifies IPv4-in-IPv6 and site-local addresses as public, allowing SSRF | |
| First Time appeared |
Ash-project
Ash-project ash Authentication Oauth2 Server |
|
| Weaknesses | CWE-918 | |
| CPEs | cpe:2.3:a:ash-project:ash_authentication_oauth2_server:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Ash-project
Ash-project ash Authentication Oauth2 Server |
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| References |
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|
| Metrics |
cvssV4_0
|
Projects
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Status: PUBLISHED
Assigner: EEF
Published:
Updated: 2026-09-08T14:43:57.511Z
Reserved: 2026-08-31T01:00:10.817Z
Link: CVE-2026-82757
Updated: 2026-09-08T14:43:53.924Z
Status : Deferred
Published: 2026-09-07T23:16:52.957
Modified: 2026-09-08T15:18:50.823
Link: CVE-2026-82757
No data.
OpenCVE Enrichment
Updated: 2026-09-08T20:36:37Z