CVE-2026-3276

MEDIUM EPSS 38.6%
Published Jun 3, 20261mo ago · Modified Jun 17, 20262w ago
6.3 CVSS 4.0
Medium
Find Similar
Published Jun 3, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

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.

CVSS Details

Base Score
6.3
Exploitability
—
Impact
—
Vector string
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
38.6% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-407

References 9

  • openwall.com http://www.openwall.com/lists/oss-security/2026/06/03/15
  • github.com https://github.com/python/cpython/commit/6b505d1f41f8f3ea0fe5a4786d3a8fff1875cfc0
  • github.com https://github.com/python/cpython/commit/90748760d38ca3ac5fc6788a69becab905c95598
  • github.com https://github.com/python/cpython/commit/991224b1e8311c85f198f6dd8208bf8cff7fc26f
  • github.com https://github.com/python/cpython/commit/ba785b88add96acbf403d65cb157fb2743a33a32
  • github.com https://github.com/python/cpython/commit/c5512bd7c1dc28055660565275012766941d3066
  • github.com https://github.com/python/cpython/issues/149079
  • github.com https://github.com/python/cpython/pull/149080
  • mail.python.org https://mail.python.org/archives/list/security-announce@python.org/thread/PP5HB4K7727OBBM76KA2ILID76K3OZGZ/

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.