Is there a public exploit for CVE-2026-123338?

No public exploit for CVE-2026-123338 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

What does CVE-2026-123338 affect?

CVE-2026-123338 affects Apache Software Foundation Apache DataSketches C++.

— Unscored

Out-of-bounds Write vulnerability in Apache DataSketches C++.

CVE-2026-123338

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.

Assessment

CVSS: Not yet scored
Severity: Unscored
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 13 November 2026
Last updated: 13 November 2026
Affected: Apache Software Foundation · Apache DataSketches C++
Assigner: apache

At the source

EUVD (ENISA)

References

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