Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%

Buy Us a Coffee

CVE-2026-82754— ash_authentication_oauth2_server aliases every protocol endpoint under /.well-known, bypassing path-scoped controls

Quick assessment

Affected

ash-project ash_authentication_oauth2_server

Exploitation

No confirmed in-the-wild exploitation; assess based on exposure

Recommended action

Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

ash-project 中 ash_authentication_oauth2_server 存在“备用路径保护不当”漏洞在 ash_authentication_oauth2_server 中，由于备用路径缺乏充分保护，导致状态变更型的 OAuth 端点暴露在非预期的 URL 前缀下，从而绕过了仅针对规范前缀设置的控制措施。具体而言，位于的在前缀和前缀下都挂载了同一个。由于 Phoenix 的机制会在分发前剥离已匹配的前缀，因此完整的路由表会在两个挂载点同时生效。这使得、和也可以分别通过、

CVSS 6.3 · Medium Updated Sep 08, 2026

Possible ATT&CK Techniques 2 AI

T1557 · Adversary-in-the-Middle T1205 · Traffic Signaling

Get alerts for future matching vulnerabilities Log in to subscribe

Vulnerability Information

Have questions about the vulnerability? See if Shenlong's analysis helps!

View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title

ash_authentication_oauth2_server aliases every protocol endpoint under /.well-known, bypassing path-scoped controls

Source: CVE Program / CVE List V5

Vulnerability Description

Improper Protection of Alternate Path vulnerability in ash-project ash_authentication_oauth2_server exposes the state-changing OAuth endpoints under an unintended URL prefix, bypassing controls scoped to the canonical prefix. oauth2_server_protocol_routes/1 in AshAuthentication.Phoenix.Oauth2Server.Router forwards the same ProtocolRouter at both the /oauth prefix and the /.well-known prefix. Phoenix forward strips the matched prefix before dispatch, so the full route table answers under both mounts, and POST /register, POST /token, and POST /revoke are reachable as /.well-known/register, /.well-known/token, and /.well-known/revoke. Edge controls such as WAF rules, rate limits, or authentication exemptions written against the /oauth paths, or that allow-list /.well-known as unauthenticated, do not apply to the alias. This issue affects ash_authentication_oauth2_server: from 0.1.0 before 0.3.1.

Source: CVE Program / CVE List V5

CVSS Information

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Source: CVE Program / CVE List V5

Vulnerability Type

对候选路径的不恰当保护

Source: CVE Program / CVE List V5

Affected Products

Vendor	Product	Affected Versions	CPE	Subscribe
ash-project	ash_authentication_oauth2_server	0.1.0 ~ 0.3.1	`cpe:2.3:a:ash-project:ash_authentication_oauth2_server::::::::`
ash-project	ash_authentication_oauth2_server	855b578037c5ded18e8a6e60f42e56bde4905fae ~ a72972d7ed3eb74c05dfa0653a258ef14454459a	`cpe:2.3:a:ash-project:ash_authentication_oauth2_server::::::::`

II. Public POCs for CVE-2026-82754

#	POC Description	Source Link	Shenlong Link

AI-Generated POC Premium

No public POC found.

III. Intelligence Information for CVE-2026-82754

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-82754 (1)

🔗 fix: don't alias state-changing OAuth endpoints under /.well-known · ash-project/ash_authentication_oauth2_server@a72972d · GitHub Read full article patch

Vendor Advisories for CVE-2026-82754 (2)

Other References for CVE-2026-82754 (1)

🔗 EEF-CVE-2026-82754 - OSV Read full article related

https://www.cve.org/CVERecord?id=CVE-2026-82754

Same Patch Batch · ash-project · 2026-09-07 · 9 CVEs total

CVE-2026-82753	8.2 HIGH	Unauthenticated authorize requests create unbounded, never-expiring CIMD client rows and c
CVE-2026-82586	8.2 HIGH	AshLua read operation aggregate bypasses the exposed-field allow-list, exposing private at
CVE-2026-82755	6.3 MEDIUM	ash_authentication_oauth2_server serves tenant-specific OAuth metadata as publicly cacheab
CVE-2026-82758	6.3 MEDIUM	ash_authentication_oauth2_server treats an empty resolved secret as valid, opening the gat
CVE-2026-82757	6.3 MEDIUM	ash_authentication_oauth2_server CIMD fetcher classifies IPv4-in-IPv6 and site-local addre
CVE-2026-82756	6.3 MEDIUM	ash_authentication_oauth2_server interpolates a tenant-derived value into the WWW-Authenti
CVE-2026-82584	2.3 LOW	Terminal escape sequence injection in the mix igniter.install confirmation prompt via pack
CVE-2026-81638	2.1 LOW	Non-canonical ULID spellings are accepted and alias to the same record in ash_double_entry

IV. Related Vulnerabilities

Same product: ash_authentication_oauth2_server

Same vendor: ash-project

Same weakness: CWE-424

V. Comments for CVE-2026-82754

No comments yet

Goal Reached Thanks to every supporter — we hit 100%!

CVE-2026-82754— ash_authentication_oauth2_server aliases every protocol endpoint under /.well-known, bypassing path-scoped controls

Quick assessment

Possible ATT&CK Techniques 2 AI

I. Basic Information for CVE-2026-82754

Vulnerability Information

Vulnerability Title

Vulnerability Description

CVSS Information

Vulnerability Type

Affected Products

II. Public POCs for CVE-2026-82754

III. Intelligence Information for CVE-2026-82754

Patches & Fixes for CVE-2026-82754 (1)

Vendor Advisories for CVE-2026-82754 (2)

Other References for CVE-2026-82754 (1)

Same Patch Batch · ash-project · 2026-09-07 · 9 CVEs total

IV. Related Vulnerabilities

V. Comments for CVE-2026-82754

Leave a comment