CVE-2026-3644

Publication date 16 March 2026

Last updated 10 September 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().

Status

Package Ubuntu Release Status
python2.7 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 2.7.18-13ubuntu1.5+esm9
20.04 LTS focal
Fixed 2.7.18-1~20.04.7+esm10
18.04 LTS bionic
Fixed 2.7.17-1~18.04ubuntu1.13+esm15
16.04 LTS xenial
Fixed 2.7.12-1ubuntu0~16.04.18+esm22
14.04 LTS trusty
Fixed 2.7.6-8ubuntu0.6+esm30
python3.4 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
14.04 LTS trusty
Fixed 3.4.3-1ubuntu1~14.04.7+esm21
python3.5 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Fixed 3.5.2-2ubuntu0~16.04.13+esm25
14.04 LTS trusty
Fixed 3.5.2-2ubuntu0~16.04.4~14.04.1+esm11
python3.6 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Fixed 3.6.9-1~18.04ubuntu1.13+esm10
python3.7 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Fixed 3.7.5-2ubuntu1~18.04.2+esm11
python3.8 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Fixed 3.8.10-0ubuntu1~20.04.18+esm7
18.04 LTS bionic
Fixed 3.8.0-3ubuntu1~18.04.2+esm11
python3.9 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Fixed 3.9.5-3ubuntu0~20.04.1+esm11
python3.10 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 3.10.12-1~22.04.16
python3.11 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 3.11.0~rc1-1~22.04.1+esm2
python3.12 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble
Fixed 3.12.3-1ubuntu0.15
22.04 LTS jammy Not in release
python3.13 26.04 LTS resolute Not in release
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
python3.14 26.04 LTS resolute
Not affected
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
python3.12

Severity score breakdown

CVSS version:

Base score 6.0 · Medium

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N

Base score 7.5 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References

Related Ubuntu Security Notices (USN)

Other references

Access our resources on patching vulnerabilities