Description
The mod_auth_shadow module 1.0 through 1.5 and 2.0 for Apache with AuthShadow enabled uses shadow authentication for all locations that use the require group directive, even when other authentication mechanisms are specified, which might allow remote authenticated users to bypass security restrictions.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗Advisories 1
- DSA-844-1 mod-auth-shadow - programming error Debian Security (DSA / DLA) · Mar 9, 2026
References
- modauthshadow-require-group-bypass-security(22520) vdb-entry
- 17348 third-party-advisory
- 19863 vdb-entry
- 17060 third-party-advisory
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=323789
- DSA-844 vendor-advisory
- MDKSA-2005:200 vendor-advisory
- 15224 vdb-entry
- 17067 third-party-advisory