Summary
pypdf: Possible large memory usage for wrong image dimensions
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3888.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires loading images where the declared size values are much too large compared to the actual data.
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
This has been fixed in pypdf==6.14.0.
Frequently Asked Questions
- What is CVE-2026-59938? CVE-2026-59938 is a medium-severity security vulnerability in pypdf (pip), affecting versions < 6.14.0. It is fixed in 6.14.0.
- Which versions of pypdf are affected by CVE-2026-59938? pypdf (pip) versions < 6.14.0 is affected.
- Is there a fix for CVE-2026-59938? Yes. CVE-2026-59938 is fixed in 6.14.0. Upgrade to this version or later.
- Is CVE-2026-59938 exploitable, and should I be worried? Whether CVE-2026-59938 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-2026-59938 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-2026-59938? Upgrade
pypdfto 6.14.0 or later.