HTTP client proxy tunnel headers not validated for CR/LF
Priority LOW 26CWE-93Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Partial Red Hat: 9 fixed, 6 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00535 45th percentileScored 2026-11-07
Fix Partial CPython (Python Software Foundation): 3.10.21, 3.11.16, 3.12.14 +3Red Hat: 11 advisoriesRed Hat: 9 fixed, 6 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Python Software Foundation | CPython | before 3.10.21; 3.11.0 to before 3.11.16; 3.12.0 to before 3.12.14; 3.13.0 to before 3.13.14; 3.14.0a1 to before 3.14.5rc1; 3.15.0a1 to before 3.15.0b1 | 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.5rc1, 3.15.0b1 | Patch available | CNA |
- CPython VendorPython Software Foundation Affected before 3.10.21; 3.11.0 to before 3.11.16; 3.12.0 to before 3.12.14; 3.13.0 to before 3.13.14; 3.14.0a1 to before 3.14.5rc1; 3.15.0a1 to before 3.15.0b1 Fixed in 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.5rc1, 3.15.0b1 Patch available CNA
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | — | — | python-pillow |
- cpe:2.3:a:python:python:*:*:*:*:*:*:*:* Versions — — ·python-pillow
Remediation
- Fix · CNA CPython (Python Software Foundation) Fixed in 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.5rc1, 3.15.0b1
Red Hat 11 advisories
- RHSA-2026:58981 Released 2026-08-24 · Red Hat rating CriticalRed Hat Update Infrastructure 5.3 Technology Preview security update
- Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-tp-rhel9, registry.redhat.io/rhui5/installer-tp-rhel9, registry.redhat.io/rhui5/rhua-tp-rhel9
- RHSA-2026:21275 Released 2026-05-27 · Red Hat rating CriticalRed Hat Update Infrastructure 5.1 security update
- Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9, registry.redhat.io/rhui5/installer-rhel9 +1
- RHSA-2026:19176 Released 2026-05-19 · Red Hat rating Importantpython3.14 security update
- Red Hat Enterprise Linux AppStream (v. 9) python3.14-3.14.4-2.el9_8, python3.14-devel-3.14.4-2.el9_8, python3.14-libs-3.14.4-2.el9_8 +1
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) python3.14-3.14.4-2.el9_8, python3.14-debug-3.14.4-2.el9_8, python3.14-freethreading-3.14.4-2.el9_8 +9
Show 8 more Red Hat advisories
- RHSA-2026:19177 Released 2026-05-19 · Red Hat rating Importantpython3.12 security update
- Red Hat Enterprise Linux AppStream (v. 9) python3.12-3.12.13-2.el9_8, python3.12-devel-3.12.13-2.el9_8, python3.12-libs-3.12.13-2.el9_8 +1
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) python3.12-3.12.13-2.el9_8, python3.12-debug-3.12.13-2.el9_8, python3.12-idle-3.12.13-2.el9_8 +2
- RHSA-2026:19064 Released 2026-05-19 · Red Hat rating Importantpython3.12 security update
- Red Hat Enterprise Linux AppStream (v. 10) python-unversioned-command-3.12.13-2.el10_2, python3-devel-3.12.13-2.el10_2, python3-tkinter-3.12.13-2.el10_2
- Red Hat Enterprise Linux BaseOS (v. 10) python3-3.12.13-2.el10_2, python3-libs-3.12.13-2.el10_2, python3.12-3.12.13-2.el10_2
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) python3-debug-3.12.13-2.el10_2, python3-idle-3.12.13-2.el10_2, python3-test-3.12.13-2.el10_2
- RHSA-2026:19019 Released 2026-05-19 · Red Hat rating Importantpython3.14 security update
- Red Hat Enterprise Linux AppStream (v. 10) python3.14-3.14.4-2.el10_2, python3.14-devel-3.14.4-2.el10_2, python3.14-libs-3.14.4-2.el10_2 +1
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) python3.14-debug-3.14.4-2.el10_2, python3.14-freethreading-3.14.4-2.el10_2, python3.14-freethreading-debug-3.14.4-2.el10_2 +7
- RHSA-2026:10950 Released 2026-04-27 · Red Hat rating Importantpython3.12 security update
- Red Hat Enterprise Linux AppStream (v. 8) python3.12-3.12.13-2.el8_10, python3.12-devel-3.12.13-2.el8_10, python3.12-libs-3.12.13-2.el8_10 +2
- Red Hat Enterprise Linux CRB (v. 8) python3.12-3.12.13-2.el8_10, python3.12-debug-3.12.13-2.el8_10, python3.12-idle-3.12.13-2.el8_10 +2
- RHSA-2026:10117 Released 2026-04-23 · Red Hat rating ImportantRed Hat Hardened Images RPMs Security Update
- Red Hat Hardened Images python3.13-3.13.13-1.1.hum1@aarch64, python3.13-3.13.13-1.1.hum1@src, python3.13-3.13.13-1.1.hum1@x86_64 +16
- RHSA-2026:9228 Released 2026-04-21 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images python-unversioned-command-3.14.4-2.hum1@noarch@public-hummingbird-aarch64-rpms, python-unversioned-command-3.14.4-2.hum1@noarch@public-hummingbird-x86_64-rpms, python3-3.14.4-2.hum1@aarch64 +28
- RHSA-2026:8824 Released 2026-04-17 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images python3.12-3.12.13-3.hum1@aarch64, python3.12-3.12.13-3.hum1@src, python3.12-3.12.13-3.hum1@x86_64 +12
- RHSA-2026:8822 Released 2026-04-17 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images python3.11-3.11.15-4.hum1@aarch64, python3.11-3.11.15-4.hum1@src, python3.11-3.11.15-4.hum1@x86_64 +12
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AI (RHEL AI) 3 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | — |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:19019, RHSA-2026:19064 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:10950 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:19176, RHSA-2026:19177 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2026:19064 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2026:10950 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2026:19019, RHSA-2026:19064 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:19176, RHSA-2026:19177 |
| Red Hat Hardened Images | Fixed | RHSA-2026:10117, RHSA-2026:8822, RHSA-2026:8824, RHSA-2026:9228 |
| Red Hat Update Infrastructure 5 | Fixed | RHSA-2026:21275, RHSA-2026:58981 |
Not affected: 1 product
- Red Hat Update Infrastructure 5
Timeline
- 2026-10-02 Threatist record created from CVE-2026-1502
- 2026-10-03 Alias added: GHSA-hjxq-7w9q-2jw6
- 2026-11-06 Affected versions changed · Red Hat
References
Patch 7
- https://github.com/python/cpython/pull/146212
- https://github.com/python/cpython/commit/05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69
- https://github.com/python/cpython/commit/b1cf9016335cb637c5a425032e8274a224f4b2ed
- https://github.com/python/cpython/commit/9e071c9b28c17f347f81b388a003d4eeb3c7a8dd
- https://github.com/python/cpython/commit/c00c386faa579ad71196d33408644478488e43ec
- https://github.com/python/cpython/commit/56b7100b04e44ea27989242b176beb8f016b2c53
- https://github.com/python/cpython/commit/58703ec1bdd1eb075e8b01a0c427683ce594dd3e
Advisory 1
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- TI-2026-04606 Possible to hijack modules in current working directory CVSS 4.0MEDIUM 5.6
Sources
- CVE-2026-1502 · CVE Program
- CVE-2026-1502 · NVD
- FIRST EPSS
- GHSA-hjxq-7w9q-2jw6 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-1502 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences