CVE-2026-84309
Description
A flaw was found in pypdf. An attacker can craft a malicious PDF document with a cyclic tree structure. When a writing code path attempts to insert a child object, the TreeObject.insert_child function can follow /Next links indefinitely, leading to an infinite loop. This can result in a denial of service (DoS) due to resource exhaustion.
Statement
This vulnerability is rated as having a Moderate severity for Red Hat because exploitation is limited to a denial of service condition without compromising data confidentiality or system integrity. In Red Hat environments incorporating pypdf—such as OpenShift AI, OpenShift Lightspeed, and Red Hat Quay—triggering this flaw requires an application to actively process and modify an untrusted, malformed document through specific tree-insertion routines. Because typical workflows do not automatically alter arbitrary document tree structures without explicit application workflows, the risk is contained to process hanging or CPU exhaustion for the affected worker process.
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
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
