What is 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.
The record classifies CVE-2026-82757 under weakness class CWE-918. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 28 days ago.
Severity and exploitation probability
- CVSS v4.0 base score
- 6.3 — Medium (derived from score)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N - EPSS (FIRST)
- 0.3% probability of exploitation in the next 30 days, higher than 30.1% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-09-07, last modified 2026-09-08
Is CVE-2026-82757 being exploited?
It currently carries a trending score of 37 in the Threadlinqs vulnerability feed.
Affected products and versions
- ash-project: ash_authentication_oauth2_server
How to fix CVE-2026-82757
No vendor patch reference has been recorded for CVE-2026-82757 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-82757
No threat campaign in the Threadlinqs corpus currently references CVE-2026-82757, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.
Sources
Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on .