pypdf: Possible infinite loop for not terminated inline images (ASCII85 and ASCIIHex filter)
Priority MEDIUM 45CWE-835Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 6 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-835.
Summary
pypdf is a free and open-source pure-python PDF library. Prior to 6.14.2, an attacker can craft a PDF with a page content stream containing a not terminated inline image that uses the ASCII85 or ASCIIHex filters, causing an infinite loop during parsing such as when extracting page text. This issue is fixed in version 6.14.2.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0062 49th percentileScored 2026-11-07
Fix Partial pypdf (py-pdf): 6.14.2pypdf (PyPI): 6.14.2Red Hat: 6 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 6.14.2 | 6.14.2 | Patch available | CNA |
| — | pypdf (PyPI) | before 6.14.2 | 6.14.2 | Patch available | GHSA-g867-7843-wf8q |
- pypdf Vendorpy-pdf Affected before 6.14.2 Fixed in 6.14.2 Patch available CNA
- pypdf (PyPI) Vendor— Affected before 6.14.2 Fixed in 6.14.2 Patch available GHSA-g867-7843-wf8q
Remediation
- Fix · CNA pypdf (py-pdf) Fixed in 6.14.2
- Fix · GHSA-g867-7843-wf8q pypdf (PyPI) Fixed in 6.14.2 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Exploit Intelligence | Affected | No fix yet: Fix deferred |
| OpenShift Lightspeed | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet: Fix deferred |
| 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 yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-59935
- 2026-10-03 Alias added: GHSA-g867-7843-wf8q
References
Patch 3
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-2026-65557 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
- TI-2026-65555 pypdf: Possible long runtimes when generating appearance streams CVSS 4.0HIGH 8.7
Sources
- CVE-2026-59935 · CVE Program
- CVE-2026-59935 · NVD
- FIRST EPSS
- GHSA-g867-7843-wf8q · GitHub Advisory Database · CC BY 4.0
- CVE-2026-59935 · 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