CVE-2026-48156 json
pypdf: Possible long runtimes for zero-only width values in cross-reference streams
published 2026-05-28 5 mo ago modified 2026-11-02 6 d ago also EUVD-2026-32913 , GHSA-248m-82v9-q6g6 , PYSEC-2026-3004
- cvss
- 3.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 2%
- public exploits
- 0
- none known
Summary
pypdf is a free and open-source pure-python PDF library. Prior to 6.12.0, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values. This vulnerability is fixed in 6.12.0.
Patch / fix
- pypi pypdf 6.12.0
- py-pdf pypdf 6.12.0
- pypdf2_project pypdf2 6.12.0
- pypdf_project pypdf 6.12.0
- pypdf Debian 14 6.19.0-1
debian advisories DEBIAN-CVE-2026-48156
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-48156 updated cvss 3.3
pypdf: pypdf: Denial of Service via crafted PDF
-
Red Hat Exploit Intelligence exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-ocp-rag-rhel9, openshift-lightspeed-tech-preview/lightspeed-rag-tool-rhel9 Red Hat Ansible Automation Platform 2 ansible-automation-platform-25/lightspeed-chatbot-rhel8 Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/disk-image-cuda-rhel9 Red Hat OpenShift AI (RHOAI) rhoai/odh-llama-stack-core-rhel9 Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9affected: workaround, no fix available “Fix deferred”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.12% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| GitHub | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
| OSV | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | pypdf | <6.12.0 |
6.12.0 |
Affected products
- py-pdf pypdf
Classification
- Weakness
-
- CWE-834 Excessive Iteration
References
-
github.com
/py-pdf/pypdf/pull/3791
web, issue-tracking, patch
-
github.com
/py-pdf/pypdf/security/advisories/GHSA-248m-82v9-q6g6
web, patch, vendor-advisory
-
github.com
/py-pdf/pypdf/commit/507d7c9aa6ea83389b954b9c3c0c528fe5d5da70
web
-
github.com
/py-pdf/pypdf/releases/tag/6.12.0
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2026-48156
advisory
-
github.com
/py-pdf/pypdf
package
-
pypi.org
/project/pypdf
package
-
github.com
/advisories/GHSA-248m-82v9-q6g6
advisory
Sources
- CVE List CVE-2026-48156
- GitHub Advisory GHSA-248m-82v9-q6g6
- NVD CVE-2026-48156
- OSV PYSEC-2026-3004
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.