CVE-2026-123274

EUVD-2026-125275
Out-of-bounds Write vulnerability in Apache DataSketches C++. An
  application that deserializes a KLL sketch from an untrusted source
  can have heap memory corrupted by a crafted sketch, because the
  serialized level boundaries were not validated.

  This issue affects Apache DataSketches C++: 2.0.0 through 5.3.0.

  Users are recommended to upgrade to version 5.3.1, which fixes the
  issue.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
UNKNOWN
---
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://github.com/apache/datasketches-cpp/commit/bb86d439db494e3d362e54cc4f83481893974335
https://github.com/apache/datasketches-cpp/pull/568
https://github.com/apache/datasketches-cpp/releases/tag/5.3.1
https://lists.apache.org/thread/t4rngyg9cbv1b42f1d0crgpgtpby0594
http://www.openwall.com/lists/oss-security/2026/11/13/1