CVE-2026-33123: py-pdf pypdf Uncontrolled Resource Consumption
CVSS: 6.5v3.1MediumAnalyzed
AliasesGHSA-qpxp-75px-xjcpPYSEC-2026-3023UBUNTU-CVE-2026-33123DEBIAN-CVE-2026-33123CGA-7j7w-9589-3f5vCGA-c9wj-r2vq-hv75openSUSE-SU-2026:10402-1openSUSE-SU-2026:10403-1openSUSE-SU-2026:20430-1CGA-3524-244f-9qr5CGA-fqcc-cjc6-462w
Published 20-03-2026Last modified 20-03-2026
Vulnerability summary
CVE-2026-33123 is a medium (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in py-pdf pypdf. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.5% of scored vulnerabilities.
CVSS score
6.5/10
010
Medium · v3.1 (NVD)EPSS score
0.39%
0%100%
Low · +0.04 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 0 · Related 1Timeline
- 20-03-2026PublishedVulnerability first disclosed.
- 20-03-2026Last modifiedVulnerability information updated.
Description
pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.1 allow an attacker to craft a malicious PDF which leads to long runtimes and/or large memory usage. Exploitation requires accessing an array-based stream with many entries. This issue has been fixed in version 6.9.1.
CVSS metrics
9 scores · 7 sources · 2 versionsMedium 5.1Preferred score · CVE.org (CNA)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NSourcesAll 6 agree
- OSV · PypiEcosystem advisory · calculated5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · UbuntuEcosystem advisory · calculated5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · WolfiEcosystem advisory · calculated5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- NVDNIST5.1MediumCVSS: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
Medium 6.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.39%
Chance of exploitation in the next 30 days
Percentile
32%
Versus all other CVEs
30-day change
+0.04 pp
From 0.35% on 20-09-2026
20-09-202620-10-2026
EPSS score0.39%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-400Uncontrolled Resource ConsumptionThe product does not properly control the allocation and maintenance of a limited resource.
- CWE-407Inefficient Algorithmic ComplexityAn algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
Affected systems
Opensuse3 products
- python-PyPDF2&distro=openSUSE Leap 16.0< 2.11.1-bp160.5.1
- python-PyPDF2&distro=openSUSE Tumbleweed< 2.11.1-8.1
- python-pypdf&distro=openSUSE Tumbleweed< 6.9.1-1.1
Chainguard2 products
- litellm< 1.82.3.0-r0
- open-webui< 0.8.12-r1 | < 0.8.12-r2
Debian2 products
- pypdfAll versions (No fix recorded) | < 6.9.2-1
- pypdf2All versions (No fix recorded)
Py-pdf1 product
- pypdf< 6.9.1
Pypdf_project1 product
- pypdf< 6.9.1
PyPI1 product
- pypdf< 6.9.1
Ubuntu1 product
- pypdfAll versions (No fix recorded)
Wolfi1 product
- open-webui< 0.8.12-r1 | < 0.8.12-r2
8 vendors · 12 products
References
13 links- github.com/py-pdf/pypdf/security/advisories/GHSA-qpxp-75px-xjcpX Refsource CONFIRMWEBREPORTAdvisoryPatchVendor Advisory
- github.com/py-pdf/pypdfPACKAGE
- pypi.org/project/pypdfPACKAGE
