Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS01aDV2LW01OTYtcjZyZs4AA8kJ

TYPO3 Possible Insecure Deserialization in Extbase Request Handling

It has been discovered that request handling in Extbase can be vulnerable to insecure deserialization. User submitted payload has to be signed with a corresponding HMAC-SHA1 using the sensitive TYPO3 encryptionKey as secret - invalid or unsigned payload is not deserialized.

However, since sensitive information could have been leaked by accident (e.g. in repositories or in commonly known and unprotected backup files), there is the possibility that attackers know the private encryptionKey and are able to calculate the required HMAC-SHA1 to allow a malicious payload to be deserialized.

Requirements for successfully exploiting this vulnerability (all of the following):

• rendering at least one Extbase plugin in the frontend
• encryptionKey has been leaked (from LocalConfiguration.php or corresponding .env file)

Permalink: https://github.com/advisories/GHSA-5h5v-m596-r6rf
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS01aDV2LW01OTYtcjZyZs4AA8kJ
Source: GitHub Advisory Database
Origin: Unspecified
Severity: High
Classification: General
Published: 8 months ago
Updated: 8 months ago

CVSS Score: 8.1
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Identifiers: GHSA-5h5v-m596-r6rf
References:

• https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms-core/2019-12-17-7.yaml
• https://typo3.org/security/advisory/typo3-psa-2019-011
• https://github.com/advisories/GHSA-5h5v-m596-r6rf

Blast Radius: 29.0

Affected Packages