CVE-2026-24688: py-pdf pypdf Infinite Loop
Vulnerability summary
CVE-2026-24688 is a medium (CVSS 5.1) Infinite Loop vulnerability in py-pdf pypdf. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.9% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 0 · Related 1Timeline
- 27-01-2026PublishedVulnerability first disclosed.
- 27-01-2026Last modifiedVulnerability information updated.
Description
pypdf is a free and open-source pure-python PDF library. An attacker who uses an infinite loop vulnerability that is present in versions prior to 6.6.2 can craft a PDF which leads to an infinite loop. This requires accessing the outlines/bookmarks. This has been fixed in pypdf 6.6.2. If projects cannot upgrade yet, consider applying the changes from PR #3610 manually.
CVSS metrics
9 scores · 7 sources · 2 versions- 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
- OSV · DebianEcosystem advisory · calculated4.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
- NVDNIST4.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
EPSS trend
Probability
0.45%
Chance of exploitation in the next 30 days
Percentile
38%
Versus all other CVEs
30-day change
+0.04 pp
From 0.41% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard2 products
- nemo< 2.6.1-r4
- open-webui< 0.8.3-r1
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)
Opensuse1 product
- python-pypdf&distro=openSUSE Tumbleweed< 6.6.2-1.1
Py-pdf1 product
- pypdf< 6.6.2
Pypdf_project1 product
- pypdf< 6.6.2
PyPI1 product
- pypdf< 6.6.2
Wolfi1 product
- open-webui< 0.8.3-r1
8 vendors · 11 products
References
13 links- github.com/py-pdf/pypdf/security/advisories/GHSA-2q4j-m29v-hq73X Refsource CONFIRMWEBREPORTAdvisoryVendor Advisory
- github.com/py-pdf/pypdf/commit/b1282f8dcdc1a7b41ceab6740ffddfdf31b1fec1X Refsource MISCWEBREPORTFIXPatch
- github.com/py-pdf/pypdfPACKAGE
- pypi.org/project/pypdfPACKAGE
