CVE-2026-103995 json
Lenient parsing of integers for response body and chunk framing
published 2026-10-27 12 d ago modified 2026-11-04 4 d ago also EUVD-2026-111382
- cvss
- 2.0
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 29%
- public exploits
- 0
- none known
Summary
Response body and chunk parsing would handle non-hex or negative integers incorrectly which could result in misinterpreting HTTP response contents.
Patch / fix
- Python Software Foundation CPython 3.16.0
- github.com/python/cpython@2eb2af8 commit
- github.com/python/cpython@9f52b44 commit
- github.com/python/cpython#150752 pull request
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-2026-103995 updated cvss 5.3
python: python: Misinterpretation of HTTP responses via invalid chunk parsing
-
Red Hat Enterprise Linux 6 python, tkinter, python-libs, python-test, python-toolsaffected: no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 7 python, python3, tkinter, python-libs, python-test, python-tools, +4 more Red Hat Enterprise Linux 8 scipy, python3, python36, python3.12, python-nose, python-wheel, +32 more Red Hat Enterprise Linux 9 python3, python3.9, python3.12, python3.14, python3-idle, python3-libs, +18 more Red Hat Enterprise Linux 10 python3.14 3.14.8-1.el10_2, python3.12 3.12.15-1.el10_2 Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/bootc-aws-cuda-rhel9, rhelai3/bootc-gcp-cuda-rhel9, rhelai3/bootc-azure-cuda-rhel9, +1 moreaffected: no fix available “Fix deferred”
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Red Hat Hardened Images python3.13 3.13.17-1.hum1, python3.14 3.14.8-1.el10_2, python3.15 3.15.2-0.1.hum1, python3.10 3.10.22-1.1.hum1, python3.11 3.11.17-1.1.hum1, python3.12 3.12.15-1.el10_2affected: no fix available, no fix planned “Will not fix”
-
Red Hat OpenShift Virtualization 4 container-native-virtualization/ocp-virt-validation-checkup-rhel9 Red Hat Self-service automation portal 2 ansible-automation-platform/bootc-automation-portal-rhel9affected: 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
- 4 d ago
Exploit prediction
0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 2.0 | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N |
| CNA | 4.0 | 2.0 | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/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 |
Affected products
- Python Software Foundation CPython
Classification
- Weakness
-
- CWE-444 Inconsistent Interpretation of HTTP Requests
References
Sources
- CVE List CVE-2026-103995
- NVD CVE-2026-103995
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.