Summary
Potential Remote Code Execution in TYPO3 with mediace extension
Meta
- CVSS:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C(9.1) - CWE-325, CWE-20, CWE-200, CWE-502
Problem
It has been discovered that an internal verification mechanism can be used to generate arbitrary checksums. This allows to inject arbitrary data having a valid cryptographic message authentication code (HMAC-SHA1) and can lead to various attack chains as described below.
- TYPO3-CORE-SA-2020-007, CVE-2020-15099: Potential Privilege Escalation
- the database server used for a TYPO3 installation must be accessible for an attacker (either via internet or shared hosting network)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C(7.5, high)
- TYPO3-CORE-SA-2016-013, CVE-2016-5091: Insecure Deserialization & Remote Code Execution
- an attacker must have access to at least one Extbase plugin or module action in a TYPO3 installation
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C(9.1, critical)
The overall severity of this vulnerability is critical (9.1) based on mentioned attack chains and the fact it does not require any privileges.
Credits
Thanks to TYPO3 security team member Oliver Hader who reported and fixed the issue.
References
Impact
The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.
CVE-2020-15086 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (7.6.5); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
In case the extension is not used and required at all, it is suggested to uninstall and remove it from the system completely. Otherwise, an updated version 7.6.5 is available from the TYPO3 extension manager, Packagist and the TYPO3 extension repository:
- https://extensions.typo3.org/extension/download/mediace/7.6.5/zip/
- https://packagist.org/packages/friendsoftypo3/mediace#7.6.5
As a precautionary measure it is advised to change encryptionKey and database credentials in typo3conf/LocalConfiguration.php.
Frequently Asked Questions
- What is CVE-2020-15086? CVE-2020-15086 is a critical-severity improper input validation vulnerability in friendsoftypo3/mediace (composer), affecting versions >= 7.6.2, < 7.6.5. It is fixed in 7.6.5. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
- How severe is CVE-2020-15086? CVE-2020-15086 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of friendsoftypo3/mediace are affected by CVE-2020-15086? friendsoftypo3/mediace (composer) versions >= 7.6.2, < 7.6.5 is affected.
- Is there a fix for CVE-2020-15086? Yes. CVE-2020-15086 is fixed in 7.6.5. Upgrade to this version or later.
- Is CVE-2020-15086 exploitable, and should I be worried? Whether CVE-2020-15086 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2020-15086 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2020-15086? Upgrade
friendsoftypo3/mediaceto 7.6.5 or later.