Shlink through 5.1.6 Mercure Token Authorization Bypass
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.4%
exploitation probability
0.4%top 66% of all CVEs
observed exploitation
nono source reports it
Shlink through 5.1.6 fails to enforce API key role restrictions when issuing Mercure subscription tokens, allowing restricted keys to subscribe to all topics. Attackers with author-only or domain-only keys can access the mercure-info endpoint to receive visit data including referrer, user agent, geolocation, and full short URL objects for URLs outside their authorization boundary.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
shlinkio · shlinkReferences
https://github.com/shlinkio/shlinkhttps://github.com/shlinkio/shlink/blob/v5.1.6/module/Rest/src/Action/MercureInfoAction.php#L26-L42https://github.com/shlinkio/shlink-common/blob/main/src/Mercure/LcobucciJwtProvider.php#L38-L41https://github.com/shlinkio/shlink/issues/2633https://www.vulncheck.com/advisories/shlink-through-5.1.6-mercure-token-authorization-bypass