Summary
mofh Vulnerable to Improper Restriction of XML External Entity Reference
The xml.etree.ElementTree module that mofh used up until version 1.0.1 implements a simple and efficient API for parsing and creating XML data. But it makes the application vulnerable to:
- Billion Laughs attack: It is a type of denial-of-service attack aimed at XML parsers. It uses multiple levels of nested entities. If one large entity is repeated with a couple of thousand chars repeatedly, the parser gets overwhelmed.
- Quadratic blowup attack: It is similar to a Billion Laughs attack. It abuses entity expansion, too. Instead of nested entities, it repeats one large entity with a couple of thousand chars repeatedly.
The Problem has been patched starting from version 1.0.1 by utilising the defusedxml package instead of xml.etree.ElementTree.
Workarounds
For this vulnerability to be exploited the user must be using a custom API URL, which has to be manually given using the api_url argument, or MyOwnFreeHost's API must be hacked. So, if the user did not use a custom API URL they should be fine, however, upgrading is still advised.
Another workaround could be to call defusedxml.defuse_stdlib() before making any requests using the client.
Impact
An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs. Typical impact: local file disclosure, server-side request forgery, or denial of service.
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.
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Frequently Asked Questions
- What is GHSA-7R9X-QRPR-3CXW? GHSA-7R9X-QRPR-3CXW is a medium-severity XML external entity injection (XXE) vulnerability in mofh (pip), affecting versions < 1.0.1. It is fixed in 1.0.1. An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs.
- Which versions of mofh are affected by GHSA-7R9X-QRPR-3CXW? mofh (pip) versions < 1.0.1 is affected.
- Is there a fix for GHSA-7R9X-QRPR-3CXW? Yes. GHSA-7R9X-QRPR-3CXW is fixed in 1.0.1. Upgrade to this version or later.
- Is GHSA-7R9X-QRPR-3CXW exploitable, and should I be worried? Whether GHSA-7R9X-QRPR-3CXW 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 GHSA-7R9X-QRPR-3CXW 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 GHSA-7R9X-QRPR-3CXW? Upgrade
mofhto 1.0.1 or later.