CVE-2023-44383

Workarounds

If you cannot upgrade for this patch, follow the pervious advice and remove svg from the supported file types.

References

• https://github.com/octobercms/october/blob/3.x/config/media.php

Credits to:

• Faris Krivic
• Okan Kurtulus
• Aldin Visnjic
• Bug Shankar

For more information

If you have any questions or comments about this advisory:

• Email us at [email protected]

A user with access to the media manager that stores SVG files could create a stored XSS attack against themselves and any other user with access to the media manager when SVG files are supported.

SVG files are supported by default in v3 for convenience; however, this has resulted in multiple mistaken vulnerability reports from security researchers. As per the documentation, if a backend user is not trusted, the advice is to remove the svg extension from the list of supported file types.

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2023-44383 has a CVSS score of 5.4 (Medium). The vector is network-reachable, low privileges required, and user interaction required. 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 (3.5.2); upgrading removes the vulnerable code path.

Kodem intelligence

The issue has been patched in v3.5.2 by including an SVG sanister. It is enabled by default for new installations but must be enabled for existing sites in the config/media.php file.

'clean_vectors' => true,

1. What is CVE-2023-44383? CVE-2023-44383 is a medium-severity cross-site scripting (XSS) vulnerability in october/system (composer), affecting versions >= 3.0.0, < 3.5.2. It is fixed in 3.5.2. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2023-44383? CVE-2023-44383 has a CVSS score of 5.4 (Medium). 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.
3. Which versions of october/system are affected by CVE-2023-44383? october/system (composer) versions >= 3.0.0, < 3.5.2 is affected.
4. Is there a fix for CVE-2023-44383? Yes. CVE-2023-44383 is fixed in 3.5.2. Upgrade to this version or later.
5. Is CVE-2023-44383 exploitable, and should I be worried? Whether CVE-2023-44383 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
6. What actually determines whether CVE-2023-44383 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.
7. How do I fix CVE-2023-44383? Upgrade october/system to 3.5.2 or later.