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TI-2026-05281 Aliases CVE-2026-6019GHSA-2755-2mm4-rm5c

BaseCookie.js_output() does not neutralize embedded characters

Priority LOW 11CWE-150Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 5 fixed, 8 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00211 11th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial CPython (Python Software Foundation): 3.13.14, 3.14.5rc1, 3.15.0b1Red Hat: 8 advisoriesRed Hat: 5 fixed, 8 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

VendorProductAffected versionsFixed inStatusSource
Python Software FoundationCPythonbefore 3.13.14; 3.14.0a1 to before 3.14.5rc1; 3.15.0a1 to before 3.15.0b13.13.14, 3.14.5rc1, 3.15.0b1Patch availableCNA
  • CPython VendorPython Software Foundation Affected before 3.13.14; 3.14.0a1 to before 3.14.5rc1; 3.15.0a1 to before 3.15.0b1 Fixed in 3.13.14, 3.14.5rc1, 3.15.0b1 Patch available CNA

CPE configurations NVD · 9

CPEVersionsRoleVendor
cpe:2.3:a:python:python:*:*:*:*:*:*:*:*before 3.13.14; 3.14.0 – 3.14.4Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha1:*:*:*:*:*:*3.15.0 alpha1Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha2:*:*:*:*:*:*3.15.0 alpha2Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha3:*:*:*:*:*:*3.15.0 alpha3Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha4:*:*:*:*:*:*3.15.0 alpha4Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha5:*:*:*:*:*:*3.15.0 alpha5Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha6:*:*:*:*:*:*3.15.0 alpha6Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha7:*:*:*:*:*:*3.15.0 alpha7Vulnerablepython-pillow
cpe:2.3:a:python:python:3.15.0:alpha8:*:*:*:*:*:*3.15.0 alpha8Vulnerablepython-pillow
  • cpe:2.3:a:python:python:*:*:*:*:*:*:*:* Versions before 3.13.14; 3.14.0 – 3.14.4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha1:*:*:*:*:*:* Versions 3.15.0 alpha1 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha2:*:*:*:*:*:* Versions 3.15.0 alpha2 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha3:*:*:*:*:*:* Versions 3.15.0 alpha3 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha4:*:*:*:*:*:* Versions 3.15.0 alpha4 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha5:*:*:*:*:*:* Versions 3.15.0 alpha5 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha6:*:*:*:*:*:* Versions 3.15.0 alpha6 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha7:*:*:*:*:*:* Versions 3.15.0 alpha7 Vulnerable ·python-pillow
  • cpe:2.3:a:python:python:3.15.0:alpha8:*:*:*:*:*:* Versions 3.15.0 alpha8 Vulnerable ·python-pillow

Remediation

  • Fix · CNA CPython (Python Software Foundation) Fixed in 3.13.14, 3.14.5rc1, 3.15.0b1

Red Hat 8 advisories

  • RHSA-2026:58420 Released 2026-08-21 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.12-3.12.14-1.hum1@aarch64, python3.12-3.12.14-1.hum1@src, python3.12-3.12.14-1.hum1@x86_64 +12
  • RHSA-2026:57660 Released 2026-08-20 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.11-3.11.16-1.hum1@aarch64, python3.11-3.11.16-1.hum1@src, python3.11-3.11.16-1.hum1@x86_64 +12
  • RHSA-2026:33885 Released 2026-06-30 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.11-3.11.15-4.3.hum1@aarch64, python3.11-3.11.15-4.3.hum1@src, python3.11-3.11.15-4.3.hum1@x86_64 +12
Show 5 more Red Hat advisories
  • RHSA-2026:32997 Released 2026-06-29 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images python3.13-3.13.14-1.1.hum1@aarch64, python3.13-3.13.14-1.1.hum1@src, python3.13-3.13.14-1.1.hum1@x86_64 +16
  • RHSA-2026:32980 Released 2026-06-29 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.12-3.12.13-3.2.hum1@aarch64, python3.12-3.12.13-3.2.hum1@src, python3.12-3.12.13-3.2.hum1@x86_64 +12
  • RHSA-2026:28581 Released 2026-06-24 · Red Hat rating Important
    python3.14 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) python3.14-3.14.5-1.el10_2, python3.14-devel-3.14.5-1.el10_2, python3.14-libs-3.14.5-1.el10_2 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) python3.14-debug-3.14.5-1.el10_2, python3.14-freethreading-3.14.5-1.el10_2, python3.14-freethreading-debug-3.14.5-1.el10_2 +7
  • RHSA-2026:28247 Released 2026-06-23 · Red Hat rating Important
    python3.14 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) python3.14-3.14.5-1.el9_8, python3.14-devel-3.14.5-1.el9_8, python3.14-libs-3.14.5-1.el9_8 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) python3.14-3.14.5-1.el9_8, python3.14-debug-3.14.5-1.el9_8, python3.14-freethreading-3.14.5-1.el9_8 +9
  • RHSA-2026:22952 Released 2026-06-03 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images python-unversioned-command-3.14.5-2.hum1@noarch@public-hummingbird-aarch64-rpms, python-unversioned-command-3.14.5-2.hum1@noarch@public-hummingbird-x86_64-rpms, python3-3.14.5-2.hum1@aarch64 +28

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat OpenShift Dev SpacesAffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:28581
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:28247
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:28581
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:28247
Red Hat Hardened ImagesFixed RHSA-2026:22952, RHSA-2026:32980, RHSA-2026:32997, RHSA-2026:33885, RHSA-2026:57660, RHSA-2026:58420

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-6019
  2. 2026-10-03 Alias added: GHSA-2755-2mm4-rm5c
  3. 2026-11-06 Affected versions changed · Red Hat

References

Exploit 1

Patch 4

Advisory 1

  • TI-2024-07037 Quadratic complexity parsing cookies with backslashes CVSS 3.1HIGH 7.5
  • TI-2024-11791 Bypass extraction filter to modify file metadata outside extraction directory CVSS 3.1MEDIUM 5.3
  • TI-2024-00411 Quoted zip-bomb protection for zipfile CVSS 3.1MEDIUM 6.2
  • TI-2026-13296 `HTTPPasswordMgr` can send saved HTTPS credentials via HTTP because of incorrect scheme matching CVSS 4.0MEDIUM 6.0
  • TI-2024-06422 Email header injection due to unquoted newlines CVSS 3.1MEDIUM 5.5
  • TI-2026-04606 Possible to hijack modules in current working directory CVSS 4.0MEDIUM 5.6
See all 83 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences