CVE-2026-27026: py-pdf pypdf
CVSS: 6.9v4.0MediumAnalyzed
AliasesGHSA-9mvc-8737-8j8hPYSEC-2026-3015UBUNTU-CVE-2026-27026DEBIAN-CVE-2026-27026CGA-2p7v-c7f7-wxg8CGA-jqvr-x5ff-6vxh
Published 20-02-2026Last modified 24-02-2026
Vulnerability summary
CVE-2026-27026 is a medium (CVSS 6.9) vulnerability in py-pdf pypdf. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 9.9% of scored vulnerabilities.
CVSS score
6.9/10
010
Medium · v4.0 (CVE.org)EPSS score
0.21%
0%100%
Low · +0.03 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 2 · Related 3Timeline
- 20-02-2026PublishedVulnerability first disclosed.
- 24-02-2026Last modifiedVulnerability information updated.
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used. This vulnerability is fixed in 6.7.1.
CVSS metrics
9 scores · 7 sources · 2 versionsMedium 6.9Preferred score · CVE.org (CNA)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NSourcesAll 6 agree
- OSV · PypiEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- OSV · UbuntuEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- OSV · WolfiEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- NVDNIST6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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 5.5Preferred score · OSV · Ubuntu (Ecosystem advisory) · calculated from vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- NVDNIST5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.21%
Chance of exploitation in the next 30 days
Percentile
10%
Versus all other CVEs
30-day change
+0.03 pp
From 0.17% on 20-09-2026
20-09-202620-10-2026
EPSS score0.21%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
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)
Chainguard1 product
- open-webui< 0.8.3-r1
Py-pdf1 product
- pypdf< 6.7.1
Pypdf_project1 product
- pypdf< 6.7.1
PyPI1 product
- pypdf< 6.7.1
Wolfi1 product
- open-webui< 0.8.3-r1
7 vendors · 9 products
References
12 links- github.com/py-pdf/pypdf/security/advisories/GHSA-9mvc-8737-8j8hX Refsource CONFIRMWEBREPORTAdvisoryPatchVendor Advisory
- github.com/py-pdf/pypdf/commit/7905842d833f899f1d3228af7e7467ad80277016X Refsource MISCWEBREPORTFIXPatch
- github.com/py-pdf/pypdfPACKAGE
- pypi.org/project/pypdfPACKAGE
