CVE-2026-33942

CRITICAL

Saloon has insecure deserialization in AccessTokenAuthenticator (object injection / RCE)

Title source: cna
STIX 2.1

Description

Saloon is a PHP library that gives users tools to build API integrations and SDKs. Versions prior to 4.0.0 used PHP's unserialize() in AccessTokenAuthenticator::unserialize() to restore OAuth token state from cache or storage, with allowed_classes => true. An attacker who can control the serialized string (e.g. by overwriting a cached token file or via another injection) can supply a serialized "gadget" object. When unserialize() runs, PHP instantiates that object and runs its magic methods (__wakeup, __destruct, etc.), leading to object injection. In environments with common dependencies (e.g. Monolog), this can be chained to remote code execution (RCE). The fix in version 4.0.0 removes PHP serialization from the AccessTokenAuthenticator class requiring users to store and resolve the authenticator manually.

Scores

CVSS v3 9.8
EPSS 0.0022
EPSS Percentile 44.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-502
Status published
Products (3)
saloon/saloon < 4.0.0
saloonphp/saloon 0 - 4.0.0Packagist
saloonphp/saloon < 4.0.0
Published Mar 26, 2026
Tracked Since Mar 26, 2026