Excessive memory and runtime in pypdf form field retrieval
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 7 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.
Summary
pypdf before 6.21.0 is affected. A crafted PDF can cause the library to use large amounts of memory or run for a long time when an application retrieves the document's form fields (CWE-407). A remote attacker with no privileges can trigger this if a user opens the file, which has a high impact on availability.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
pypdf is a free and open-source pure-python PDF library. Prior to 6.21.0, an attacker can craft a PDF that causes large memory usage or long runtimes when an application retrieves the document's form fields. This issue is fixed in version 6.21.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| py-pdf | pypdf | before 6.21.0 | 6.21.0 | Patch available | CNA |
| — | pypdf (PyPI) | before 6.21.0 | 6.21.0 | Patch available | GHSA-6vvc-x485-93v7 |
- pypdf Vendorpy-pdf Affected before 6.21.0 Fixed in 6.21.0 Patch available CNA
- pypdf (PyPI) Vendor— Affected before 6.21.0 Fixed in 6.21.0 Patch available GHSA-6vvc-x485-93v7
Remediation
Upgrade the PyPI pypdf package to version 6.21.0 or later. Red Hat lists Ansible Automation Platform 2 and Red Hat Quay 3 with no fix planned, and Ansible Automation Orchestrator 2026, Lightspeed Core, OpenShift Lightspeed, Red Hat Enterprise Linux AI (RHEL AI) 3 and Red Hat OpenShift AI (RHOAI) with no fix available.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA pypdf (py-pdf) Fixed in 6.21.0
- Fix · GHSA-6vvc-x485-93v7 pypdf (PyPI) Fixed in 6.21.0 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Ansible Automation Orchestrator 2026 | Affected | No fix yet: Fix deferred |
| Lightspeed Core | Affected | No fix yet: Fix deferred |
| OpenShift Lightspeed | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AI (RHEL AI) 3 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat Quay 3 | Affected | No fix planned: Out of support scope |
Timeline
- 2026-10-21 Threatist record created from CVE-2026-113789
- 2026-10-22 Affected versions changed · Red Hat
- 2026-10-22 CVSS score added · Red Hat
- 2026-10-22 Alias added: GHSA-6vvc-x485-93v7
- 2026-10-22 Fix available: PyPI/[email protected] · GHSA-6vvc-x485-93v7
- 2026-10-22 CVSS score added · GHSA-6vvc-x485-93v7
- 2026-10-22 Weakness changed · GHSA-6vvc-x485-93v7
- 2026-10-22 6 new references · GHSA-6vvc-x485-93v7
- 2026-10-23 Priority changed: MEDIUM → LOW
- 2026-10-28 CISA SSVC decision points changed
- 2026-11-02 CVSS score added · NVD
References
Patch 2
Advisory 2
More py-pdf Pypdf vulnerabilities
- TI-2023-18601 Infinite Loop when reading malformed objects in pypdf CVSS 3.1MEDIUM 6.5
- TI-2023-18305 Infinite Loop when a comment isn't followed by a character in pypdf CVSS 3.1MEDIUM 6.2
- TI-2026-42743 pypdf: Possible infinite loop for not terminated inline images CVSS 4.0HIGH 8.7
- TI-2026-42742 pypdf: Possible infinite loop for not terminated inline images (ASCII85 and ASCIIHex filter) CVSS 4.0HIGH 8.7
- TI-2026-65557 pypdf: Possible large memory usage when retrieving alphabetical page labels CVSS 4.0HIGH 8.7
- TI-2026-65556 pypdf: Possible long runtimes with large amount of embedded files CVSS 4.0HIGH 8.7
Sources
- CVE-2026-113789 · CVE Program
- CVE-2026-113789 · NVD
- FIRST EPSS
- GHSA-6vvc-x485-93v7 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-113789 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences