Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Saloon (saloonphp/saloon) versions before 4.0.0 are affected through the AccessTokenAuthenticator class, which uses PHP unserialize() to restore OAuth token state from cache or storage. An attacker who can control the serialized data, such as by overwriting a cached token file, could inject an object that runs code when unserialized, potentially leading to remote code execution when common dependencies are present. Upgrade to Saloon 4.0.0 or later; the upgrade guide is referenced in the source, and the fix removes PHP serialization from this class.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.1 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0065, the 51st percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:25 UTC First seen by agentprime
- 31 Oct 2026, 14:25 UTC Confirmed by OSV