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  4. CVE 2026 123338 apache datasketches c out of bounds write in req
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Back to active CVEs
Unknown severity · Source severity not reportedCVE-2026-123338

Apache DataSketches C++: Out-of-bounds write in REQ sketch deserialization allows memory corruption via a crafted sketchCVE-2026-123338

Answer in brief

CVE-2026-123338 records a Unknown severity vulnerability in Apache DataSketches C++: Out-of-bounds write in REQ sketch deserialization allows memory corruption via a crafted sketch. The current sources do not mark it as known exploited. The current feed maps Apache Software Foundation/apache/datasketches-cpp (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Nov 13, 2026Updated Nov 13, 2026Source checked Nov 13, 2026First seen by HOL Nov 13, 2026Material review Nov 13, 2026
Upstream Advisory

Key facts

Risk
Unknown severitySource severity not reported
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Apache Software Foundation/apache/datasketches-cpp (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Apache Software Foundation/apache/datasketches-cppgeneric>=3.0.0 <=5.3.0Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Apache Software Foundation/apache/datasketches-cpp.
  2. 2Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

  1. Published upstream

    Nov 13, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Nov 13, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Nov 13, 2026

Sources and claim methodology

  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
  • Source referencelists.apache.org
Upstream source description

Out-of-bounds Write vulnerability in Apache DataSketches C++. An application that deserializes a REQ sketch from an untrusted source can have heap memory corrupted by a crafted sketch, because the serialized compactor headers were not validated. This issue affects Apache DataSketches C++: from 3.0.0 through 5.3.0. Users are recommended to upgrade to version 5.3.1, which fixes the issue.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • Apache DataSketches C++: Out-of-bounds write in KLL sketch deserialization allows memory corruption via a crafted sketchSame apache software foundation/apache/datasketches-cpp package

Record context

Vulnerability class
Memory Corruption
EPSS
Not reported
CWE IDs
CWE-787
Source
CVE List V5
Source checked
Nov 13, 2026
References
4 linked sources
Open source record