CVE-2026-57204
Description
A flaw was found in pypdf, a pure-python PDF library. A remote attacker could exploit this vulnerability by crafting a malicious PDF file that, when parsed, leads to uncontrolled resource consumption and large memory usage. This occurs because the library sometimes ignores defined limits for stream lengths when a content stream lacks a /Length value. Successful exploitation could result in a Denial of Service (DoS) condition, making the system or application unavailable.
Statement
This Moderate flaw in pypdf can lead to a Denial of Service (DoS) due to uncontrolled memory consumption when processing a specially crafted PDF file. The vulnerability arises from the library's failure to properly enforce stream length limits in certain scenarios, allowing an attacker to exhaust system resources. Red Hat products that process untrusted PDF content, such as Red Hat Enterprise Linux AI, Red Hat Quay, Red Hat Ansible Automation Platform, and OpenShift Lightspeed, are affected if they handle untrusted PDF inputs.
Mitigation
To mitigate this issue, Red Hat recommends avoiding the processing of untrusted PDF files with applications utilizing the pypdf library. Additionally, deploying applications that handle PDF content within a sandboxed environment can limit the potential impact of successful exploitation.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | 6.5 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | Required | Required | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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