CVE-2026-28351: py-pdf pypdf Uncontrolled Resource Consumption
Vulnerability summary
CVE-2026-28351 is a medium (CVSS 6.9) Uncontrolled Resource Consumption vulnerability in py-pdf pypdf. EPSS estimates a 0.55% chance of exploitation in the next 30 days, higher than 45% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 1 · Related 2Timeline
- 27-02-2026PublishedVulnerability first disclosed.
- 03-03-2026Last modifiedVulnerability information updated.
Description
pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.4, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream using the RunLengthDecode filter. This has been fixed in pypdf 6.7.4. As a workaround, consider applying the changes from PR #3664.
CVSS metrics
9 scores · 7 sources · 2 versions- OSV · PypiEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · UbuntuEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · WolfiEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- NVDNIST6.9MediumCVSS:4.0/AV:N/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
- OSV · DebianEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS trend
Probability
0.55%
Chance of exploitation in the next 30 days
Percentile
45%
Versus all other CVEs
30-day change
+0.12 pp
From 0.42% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard3 products
- litellm< 1.81.14-r0
- nemo< 2.7.0-r1
- open-webui< 0.8.6-r0
Debian2 products
- pypdfAll versions (No fix recorded) | < 6.9.0-1
- pypdf2All versions (No fix recorded)
Ubuntu2 products
- pypdfAll versions (No fix recorded)
- pypdf2All versions (No fix recorded)
Py-pdf1 product
- pypdf< 6.7.4
Pypdf_project1 product
- pypdf< 6.7.4
PyPI1 product
- pypdf< 6.7.4
Wolfi1 product
- open-webui< 0.8.6-r0
7 vendors · 11 products
References
12 links- github.com/py-pdf/pypdf/security/advisories/GHSA-f2v5-7jq9-h8cgX Refsource CONFIRMWEBREPORTAdvisoryPatchVendor Advisory
- github.com/py-pdf/pypdf/commit/f309c6003746414dc7b5048c19e6d879ff2dc858X Refsource MISCWEBREPORTFIXPatch
- github.com/py-pdf/pypdfPACKAGE
- pypi.org/project/pypdfPACKAGE
