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  4. CVE 2026 103501 apache datasketches datasketches cpp hll
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Back to active CVEs
Unknown severity · Source severity not reportedCVE-2026-103501

Apache DataSketches: datasketches-cpp: HLL CouponList Deserialization Buffer Overflow allows memory corruption via a crafted sketchCVE-2026-103501

Answer in brief

CVE-2026-103501 records a Unknown severity vulnerability in Apache DataSketches: datasketches-cpp: HLL CouponList Deserialization Buffer Overflow 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 Oct 10, 2026Updated Oct 10, 2026Source checked Oct 10, 2026First seen by HOL Oct 10, 2026Material review Oct 10, 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>=1.0.0-incubating <=5.2.0Not 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

    Oct 10, 2026

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

  2. Source modified

    Oct 10, 2026

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

  3. First seen by HOL

    Oct 10, 2026

Sources and claim methodology

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

Heap buffer overflow in the HLL sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp). When deserializing a sketch in LIST mode, from either a byte buffer or a stream, the coupon count was read from the input and used as the number of entries to copy into a fixed buffer of 8 entries, without checking it against the buffer's capacity. A crafted sketch could cause a write of up to 988 bytes past the end of this internal heap buffer. This can corrupt heap memory, causing a crash and potentially enabling further exploitation. This issue affects Apache DataSketches C++: from 1.0.0-incubating before 5.3.0. Only applications that deserialize HLL sketches from untrusted sources are affected. Users are recommended to upgrade to version 5.3.0, which fixes this issue.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • Apache DataSketches: datasketches-cpp: Out-of-bounds read and write in the CPC sketch deserialization allows memory corruption via a crafted sketchSame apache software foundation/apache/datasketches-cpp package
  • Apache DataSketches: datasketches-cpp: Out-of-bounds read in compact Theta sketch deserialization allows denial of service via a crafted sketchSame apache software foundation/apache/datasketches-cpp package
  • Apache DataSketches: datasketches-cpp: Out-of-bounds read in VarOpt union deserialization allows denial of service via a truncated sketchSame apache software foundation/apache/datasketches-cpp package
  • FunnelKit <= 3.16.0.5 - Unauthenticated Stored Cross-Site Scripting via Order Fields (shipping/billing)Same generic ecosystem
  • WPAdverts <= 2.3.4 - Unauthenticated Stored Cross-Site Scripting via 'adverts_location' ParameterSame generic ecosystem
  • Molongui Authorship <= 5.2.12 - Unauthenticated Stored DOM-Based Cross-Site Scripting via Comment href AttributeSame generic ecosystem

Record context

Vulnerability class
Deserialization
EPSS
Not reported
CWE IDs
CWE-122, CWE-1284
Source
CVE List V5
Source checked
Oct 10, 2026
References
2 linked sources
Open source record