CVE-2026-119203
Description
A flaw was found in pypdf. This vulnerability allows an attacker to cause a Denial of Service (DoS) by tricking a user or application into processing a specially crafted PDF document. When the library parses an incomplete file where the cross-reference table ends without a trailer, the parser repeatedly rewinds to the same position instead of terminating. This behavior triggers an infinite loop, hanging the processing thread and rendering the application unresponsive.
Statement
This vulnerability is evaluated as having Moderate severity for Red Hat environments because exploitation is constrained to a denial of service and requires an application to ingest an untrusted, malformed document. Within Red Hat solutions incorporating this library—such as retrieval-augmented generation pipelines or document processing services—triggering the flaw can consume worker execution threads and degrade responsiveness. However, the issue does not allow privilege escalation, unauthorized data access, or code execution.
Mitigation
Upgrade pypdf to 6.21.4. As a workaround, apply the PR #4289 changes or avoid processing untrusted or incomplete PDF files.
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 | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | 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:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/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: Amplification
An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.
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