CVE-2026-71209
HIGH NUCLEIaudiobookshelf: %2F Encoding Discrepancy Bypasses Cover/Image Auth Exemption Regex, Enabling Unauthenticated Path Traversal
Title source: cnaExploitation Summary
CVE-2026-71209 has a Nuclei detection template available — see the Nuclei card below for the Shodan/FOFA recon queries.
Description
audiobookshelf's authentication-exemption check (server/routers/Auth.js) matches unauthenticated-allowed GET routes against req.path via a regex requiring a literal /items/:id/cover or /authors/:id/image shape, where req.path retains %2F sequences URL-encoded. CacheManager.handleCoverCache then joins this decoded value into a cache file path and streams the result before any database-backed ownership check.
Nuclei Templates (1)
Audiobookshelf - Authentication Bypass
CRITICALVERIFIEDby str4k3r
Shodan:
title:"audiobookshelf"
FOFA:
title="audiobookshelf"
References (2)
Core 2
Core References
third-party-advisory
https://github.com/advplyr/audiobookshelf/security/advisories/GHSA-pg8v-5jcv-wrvw
third-party-advisory
https://github.com/advplyr/audiobookshelf
Scores
CVSS v3
7.5
EPSS
0.0176
EPSS Percentile
75.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-22
Status
published
Products (1)
advplyr/audiobookshelf
2.19.1 - 2.35.1
Published
Aug 05, 2026
Tracked Since
Aug 05, 2026