Critical severity · published Aug 21, 2026
CVE-2026-77806
SPIP before 4.4.21 allows unauthenticated remote attackers to execute arbitrary code, as exploited in the wild in August 2026
9.8
CVSS
4.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.5% · higher than 91% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SP
SPIP · SPIP
before 4.4.21 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77806
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77806
blog.spip.net
https://blog.spip.net/Mise-a-jour-critique-de-securite-sortie-de-SPIP-4-4-21.html
github.com
https://github.com/rapid7/metasploit-framework/pull/21790
github.com
https://github.com/rapid7/metasploit-framework/pull/21790#issuecomment-5368038123
github.com
https://github.com/rapid7/metasploit-framework/pull/21790/commits/b16eca819abb8f1401f21d115e71e3dfc67b847c
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