CVE-2026-77806: Spip

Critical severity, CVSS 9.8. EPSS: 4.5% chance of exploitation in the next 30 days.

SPIP before 4.4.21 allows unauthenticated remote attackers to execute arbitrary code, as exploited in the wild in August 2026. This is related to code injection via an X-Spip-Filtre HTTP request header that is mishandled by analyse_resultat_skel.

Affected products

• Spip Spip: before 4.4.21 (fixed in 4.4.21)

Published 2026-08-21. Last modified 2026-09-08.