CVE-2025-31129
jooby-pac4j: deserialization of untrusted data
Description
### Impact Versions after 2.x and before 3.x of io.jooby:jooby-pac4j can cause deserialization of untrusted data ### Patches - 2.17.0 (2.x) - 3.7.0 (3.x) ### Workarounds - Not using io.jooby:jooby-pac4j until it gets patches. - Check what values you put/save on session ### References Version 2.x: https://github.com/jooby-project/jooby/blob/v2.x/modules/jooby-pac4j/src/main/java/io/jooby/internal/pac4j/SessionStoreImpl.java#L39-L45 Version 3.x: https://github.com/jooby-project/jooby/blob/v3.6.1/modules/jooby-pac4j/src/main/java/io/jooby/internal/pac4j/SessionStoreImpl.java#L77-L84 ### Cause In module pac4j io.jooby.internal.pac4j.SessionStoreImpl#get , it is used to handle sessions , and trying to get key value. In strToObject function ,it's trying to deserialize value when value starts with "b64~" , which might cause deserialization of untrusted data. [modules/jooby-pac4j/src/main/java/io/jooby/internal/pac4j/SessionStoreImpl.java](https://github.com/jooby-project/jooby/blob/v3.6.1/modules/jooby-pac4j/src/main/java/io/jooby/internal/pac4j/SessionStoreImpl.java#L77-L84) Here's a small demo using SessionStoreImpl#get to handle sessions ,and user can pass parameters.  And following below is exploiting successfully(execute calculator) 
How to fix CVE-2025-31129
To remediate CVE-2025-31129, upgrade the affected package to a fixed version below.
- —upgrade to 2.17.0 or later
Is CVE-2025-31129 being exploited?
Low — EPSS is 0.5%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 2.17.0