CVE-2026-113793
Description
A flaw was found in pypdf. This vulnerability allows a remote attacker to cause a Denial of Service (DoS) by providing a specially crafted PDF document containing cyclic tree structures. When an application attempts to remove an object from the cyclic structure, the library enters an infinite loop, causing the process to hang and become unresponsive.
Statement
This vulnerability is evaluated as Moderate severity because, while an attacker-supplied PDF can trigger an infinite loop and stall application execution, it cannot be leveraged to compromise confidentiality or execute arbitrary code. In Red Hat environments, pypdf is utilized within automated document ingestion and retrieval-augmented generation pipelines. Exploitation is constrained to workloads that parse untrusted files and explicitly perform tree modification operations, limiting the impact to worker process unavailability.
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 | 4.3 | N/A |
| Attack Vector | Local | 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 | Low | 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:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
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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