CVE-2026-15308

Publication date 9 July 2026

Last updated 10 September 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.

Status

Package Ubuntu Release Status
python2.7 26.04 LTS resolute 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
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
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
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
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
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
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
24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 3.10.12-1~22.04.18
python3.11 26.04 LTS resolute 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
24.04 LTS noble
Fixed 3.12.3-1ubuntu0.17
22.04 LTS jammy Not in release
python3.14 26.04 LTS resolute
Fixed 3.14.4-1ubuntu0.2
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

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Severity score breakdown

CVSS version:

Base score 8.7 · High

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-8744-1
    • Python vulnerabilities
    • 10 September 2026

Other references

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