SPIP 2.x before 2.1.19, 3.0.x before 3.0.22, and 3.1.x before 3.1.1 allows remote attackers to execute arbitrary PHP code by adding content, related to the filtrerentites function.
The encodercontexteajax function in ecrire/inc/filtres.php in SPIP 2.x before 2.1.19, 3.0.x before 3.0.22, and 3.1.x before 3.1.1 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via a crafted serialized object.
SPIP 3.0.x before 3.0.9, 2.1.x before 2.1.22, and 2.0.x before 2.0.23 allows remote attackers to gain privileges and "take editorial control" via vectors related to ecrire/inc/filtres.php.
Cross-site scripting (XSS) vulnerability in the author page (prive/formulaires/editerauteur.php) in SPIP before 2.1.24 and 3.0.x before 3.0.12 allows remote attackers to inject arbitrary web script or HTML via the urlsite parameter.