CVE-2026-123338
Apache DataSketches C++: Out-of-bounds write in REQ sketch deserialization allows memory corruption via a crafted sketch
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.
Key facts
- Published
- 13 Nov 2026
- Last changed
- 13 Nov 2026
- Assigned by
- apache
- EPSS
- 0.228% likely to be exploited in the next 30 days, higher than 13.634% of CVEs (scores for 15 Nov 2026)
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache DataSketches C++ |
|
Timeline
- 13 Nov 2026 Published