CVE-2026-49460: CWE-407: Inefficient Algorithmic Complexity in py-pdf pypdf
pypdf is a free and open-source pure-python PDF library. Prior to 6.12.2, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor. This vulnerability is fixed in 6.12.2.
AI Analysis
Technical Summary
The vulnerability CVE-2026-49460 affects the pypdf library, a pure-Python PDF processing tool. An attacker can craft a PDF file that triggers inefficient algorithmic complexity during the decoding of streams filtered with /FlateDecode and a PNG predictor, leading to prolonged processing times. This can cause denial of service conditions due to resource exhaustion. The issue is resolved in pypdf version 6.12.2.
Potential Impact
An attacker who can supply a malicious PDF to an application using a vulnerable pypdf version can cause the application to experience long processing times, potentially leading to denial of service. There is no indication of code execution or data corruption from the provided data.
Mitigation Recommendations
Upgrade pypdf to version 6.12.2 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated. Patch status is confirmed fixed in 6.12.2.
CVE-2026-49460: CWE-407: Inefficient Algorithmic Complexity in py-pdf pypdf
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.12.2, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor. This vulnerability is fixed in 6.12.2.
CVSS v4.0
Score 5.1medium
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-49460 affects the pypdf library, a pure-Python PDF processing tool. An attacker can craft a PDF file that triggers inefficient algorithmic complexity during the decoding of streams filtered with /FlateDecode and a PNG predictor, leading to prolonged processing times. This can cause denial of service conditions due to resource exhaustion. The issue is resolved in pypdf version 6.12.2.
Potential Impact
An attacker who can supply a malicious PDF to an application using a vulnerable pypdf version can cause the application to experience long processing times, potentially leading to denial of service. There is no indication of code execution or data corruption from the provided data.
Mitigation Recommendations
Upgrade pypdf to version 6.12.2 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated. Patch status is confirmed fixed in 6.12.2.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-30T02:43:33.107Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a39a0f5eed863c81e6b01e7
Added to database: 06/22/2026, 20:54:13 UTC
Last enriched: 06/29/2026, 21:50:36 UTC
Last updated: 08/06/2026, 00:41:13 UTC
Views: 59
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.