CVE-2026-3276
Publication date 3 June 2026
Last updated 18 June 2026
Ubuntu priority
Description
unicodedata.normalize() can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| python3.13 | 26.04 LTS resolute | Not in release |
| 25.10 questing |
Needs evaluation
|
|
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| python3.14 | 26.04 LTS resolute |
Needs evaluation
|
| 25.10 questing |
Needs evaluation
|
|
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| pypy3 | 26.04 LTS resolute |
Needs evaluation
|
| 25.10 questing |
Needs evaluation
|
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
|
| 14.04 LTS trusty |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| python3.12 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy | Not in release | |
| 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 |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 14.04 LTS trusty |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 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 |
Needs evaluation
|
Severity score breakdown
CVSS version: CVSS v4.0
Base score
6.3 · Medium
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
References
Other references
- https://www.cve.org/CVERecord?id=CVE-2026-3276
- https://www.openwall.com/lists/oss-security/2026/06/03/15
- https://github.com/python/cpython/pull/149080
- https://github.com/python/cpython/commit/991224b1e8311c85f198f6dd8208bf8cff7fc26f (main)
- https://github.com/python/cpython/commit/c5512bd7c1dc28055660565275012766941d3066 (v3.15.0b2)
- https://github.com/python/cpython/commit/6b505d1f41f8f3ea0fe5a4786d3a8fff1875cfc0 (3.14 branch)
- https://github.com/python/cpython/commit/ba785b88add96acbf403d65cb157fb2743a33a32 (3.13 branch)