Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-08-07T18:53:46 pypdf: pypdf: Denial of Service via crafted PDF with large CID font width ranges 5.5 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H CWE-1050

pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause long runtimes and large memory consumption when pypdf/_font.py function Font._collect_cid_character_widths expands unusually large CID font /W width ranges or excessive width entries during text extraction. This issue is fixed in 6.15.0.

A flaw was found in pypdf. A remote attacker could provide a specially crafted PDF file that, when processed by the Font._collect_cid_character_widths function during text extraction, causes the library to expand unusually large font width ranges. This can lead to excessive memory consumption and long processing times, resulting in a denial of service.

This Moderate impact denial-of-service vulnerability in the pypdf library can lead to excessive memory consumption and long runtimes when processing specially crafted PDF files. This issue affects Red Hat products that handle untrusted PDF input, potentially causing service disruption due to resource exhaustion. Exploitation requires local access or a user to process a malicious PDF. To reduce exposure, avoid processing untrusted PDF documents with applications that integrate the pypdf library. Implement robust input validation and sanitization for all PDF files originating from external or unverified sources. Consider deploying applications that process PDF content within a sandboxed environment to contain potential denial of service impacts. Exploit Intelligence Out of support scope exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 Lightspeed Core Fix deferred lightspeed-core/lightspeed-stack-rhel9 Lightspeed Core Fix deferred lightspeed-core/rag-tool-cpu-rhel9 Lightspeed Core Fix deferred lightspeed-core/rag-tool-cuda-12.9-rhel9 OpenShift Lightspeed Fix deferred openshift-lightspeed/lightspeed-ocp-rag-rhel9 OpenShift Lightspeed Fix deferred openshift-lightspeed-tech-preview/lightspeed-rag-tool-rhel9 Red Hat Ansible Automation Platform 2 Out of support scope ansible-automation-platform-25/lightspeed-chatbot-rhel8 Red Hat Enterprise Linux AI (RHEL AI) 3 Fix deferred rhelai3/bootc-cuda-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Fix deferred rhelai3/bootc-gaudi-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Fix deferred rhelai3/bootc-rocm-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Fix deferred rhelai3/disk-image-cuda-rhel9 Red Hat OpenShift AI (RHOAI) Fix deferred rhoai/odh-llama-stack-core-rhel9 Red Hat Quay 3 Out of support scope quay/quay-rhel8 Red Hat Quay 3 Fix deferred quay/quay-rhel9 https://www.cve.org/CVERecord?id=CVE-2026-71852 https://nvd.nist.gov/vuln/detail/CVE-2026-71852 https://github.com/py-pdf/pypdf/commit/51cb6acf9e8a35b77e90b4d87d28fe3e1416d7d7 https://github.com/py-pdf/pypdf/pull/3946 https://github.com/py-pdf/pypdf/releases/tag/6.15.0 https://github.com/py-pdf/pypdf/security/advisories/GHSA-fwg2-594c-jp42