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Vulnerability record · CVE-2026-77138 · published 25 August 2026

CVE-2026-77138: Deserialization of untrusted data vulnerability

The extension fails to safely process untrusted client input of an attacker-controlled cookie directly to PHP's unserialize(). A remote, unauthenticated attacker can supply a crafted serialized payload to trigger PHP Object Injection, leading to Remote Code Execution on the TYPO3 server.

9.3 CVSS 4.0 Critical EPSS 0.72% · top 48.1% CWE-502 · Deserialization of untrusted data Deferred
9.3CVSS 4.0 base score
0.72%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
26 Aug 2026Last modified by NVD

Description

The extension fails to safely process untrusted client input of an attacker-controlled cookie directly to PHP's unserialize(). A remote, unauthenticated attacker can supply a crafted serialized payload to trigger PHP Object Injection, leading to Remote Code Execution on the TYPO3 server.

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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

References

LinkTags
https://typo3.org/security/advisory/typo3-ext-sa-2026-014

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Source: NIST National Vulnerability Database (record CVE-2026-77138), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.