CVE-2026-41168: CWE-834: Excessive Iteration in py-pdf pypdf
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply the changes from the patch manually.
AI Analysis
Technical Summary
The vulnerability CVE-2026-41168 affects pypdf, a pure-Python PDF library, where an attacker can craft a PDF with cross-reference streams having incorrect large `/Size` values or object streams with incorrect large `/N` values. When pypdf versions prior to 6.10.1 process these PDFs, it results in excessive iteration causing long runtimes. This can degrade performance or cause denial of service conditions. The issue is addressed in pypdf 6.10.1, which includes a fix to handle such malformed streams properly.
Potential Impact
An attacker can cause the pypdf library to consume excessive processing time by supplying specially crafted PDF files. This may lead to denial of service or degraded performance in applications using vulnerable versions of pypdf. There is no indication of code execution or data corruption from the provided information.
Mitigation Recommendations
Upgrade to pypdf version 6.10.1 or later where this vulnerability is fixed. Alternatively, manually apply the patch changes referenced in the fix if upgrading is not immediately possible. Patch status is confirmed by the vendor advisory stating the issue is fixed in version 6.10.1.
CVE-2026-41168: CWE-834: Excessive Iteration in py-pdf pypdf
Description
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply the changes from the patch manually.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-41168 affects pypdf, a pure-Python PDF library, where an attacker can craft a PDF with cross-reference streams having incorrect large `/Size` values or object streams with incorrect large `/N` values. When pypdf versions prior to 6.10.1 process these PDFs, it results in excessive iteration causing long runtimes. This can degrade performance or cause denial of service conditions. The issue is addressed in pypdf 6.10.1, which includes a fix to handle such malformed streams properly.
Potential Impact
An attacker can cause the pypdf library to consume excessive processing time by supplying specially crafted PDF files. This may lead to denial of service or degraded performance in applications using vulnerable versions of pypdf. There is no indication of code execution or data corruption from the provided information.
Mitigation Recommendations
Upgrade to pypdf version 6.10.1 or later where this vulnerability is fixed. Alternatively, manually apply the patch changes referenced in the fix if upgrading is not immediately possible. Patch status is confirmed by the vendor advisory stating the issue is fixed in version 6.10.1.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-17T16:34:45.525Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e9371d19fe3cd2cdefb1f0
Added to database: 4/22/2026, 9:01:17 PM
Last enriched: 4/22/2026, 9:16:11 PM
Last updated: 4/23/2026, 2:43:08 AM
Views: 11
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