CVE-2026-41313
pypdf: Possible long runtimes for wrong size values in incremental mode
Description
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to long runtimes. This requires loading a PDF with a large trailer `/Size` value in incremental mode. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.
INFO
Published Date :
April 22, 2026, 10:16 p.m.
Last Modified :
April 27, 2026, 7:30 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update pypdf to version 6.10.2 or later.
- Apply patch manually if update is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-41313.
| URL | Resource |
|---|---|
| https://github.com/py-pdf/pypdf/commit/c50a0104cf083356f7c7f5d61410466a57f5c88a | Patch |
| https://github.com/py-pdf/pypdf/pull/3735 | Issue Tracking Patch |
| https://github.com/py-pdf/pypdf/releases/tag/6.10.2 | Release Notes |
| https://github.com/py-pdf/pypdf/security/advisories/GHSA-4pxv-j86v-mhcw | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-41313 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-41313
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-41313 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-41313 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* versions up to (excluding) 6.10.2 Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/commit/c50a0104cf083356f7c7f5d61410466a57f5c88a Types: Patch Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/pull/3735 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/releases/tag/6.10.2 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/security/advisories/GHSA-4pxv-j86v-mhcw Types: Patch, Vendor Advisory -
New CVE Received by [email protected]
Apr. 22, 2026
Action Type Old Value New Value Added Description pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to long runtimes. This requires loading a PDF with a large trailer `/Size` value in incremental mode. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-834 Added Reference https://github.com/py-pdf/pypdf/commit/c50a0104cf083356f7c7f5d61410466a57f5c88a Added Reference https://github.com/py-pdf/pypdf/pull/3735 Added Reference https://github.com/py-pdf/pypdf/releases/tag/6.10.2 Added Reference https://github.com/py-pdf/pypdf/security/advisories/GHSA-4pxv-j86v-mhcw