What’s Vulnerable › Vulnerabilities

CVE-2025-24856

• Severity: medium (CVSS 4.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-03-16 · updated 2026-06-17
• Weakness: CWE-348

Description

An issue was discovered in the oidc (aka OpenID Connect Authentication) extension before 4.0.0 for TYPO3. The account linking logic allows a pre-hijacking attack, leading to Account Takeover. The attack can only be exploited if the following requirements are met: (1) an attacker can anticipate the e-mail address of the user, (2) an attacker can register a public frontend user account using that e-mail address before the user's first OIDC login, and (3) the IDP returns an email field containing the e-mail address of the user,

Affected products

• TYPO3 oidc: before 4.0.0 — fixed in 4.0.0

How to fix

Upgrade to a fixed version: TYPO3 oidc 4.0.0. Check the vendor advisory for mitigations.

References

• https://github.com/xperseguers/t3ext-oidc/commit/877e09f6faf4c87bbb41233112ec7e30d3c902b3
• https://typo3.org/security/advisory/typo3-ext-sa-2025-001

Get alerted when CVE-2025-24856 or the next vulnerability affects your stack