CVE-2026-123274: Apache DataSketches C++: Out-of-bounds write in KLL sketch deserialization allows memory corruption via a crafted sketch
Noroxi assessment
Priority: Monitor (action score 0/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Fixed version: Apache Software Foundation Apache DataSketches C++ 5.3.1.
Low priority for now. Upgrade to Apache Software Foundation Apache DataSketches C++ 5.3.1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
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.
- Published
- Nov 13, 2026
- Updated
- Nov 13, 2026
- EPSS
- —
- CWE
- CWE-787
Report tools
Action score
0
Low priority for now.
- CVSS
- 0 / 40 · —
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · —
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
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What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
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Versions reported by the vendor
Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.
Apache Software Foundation Apache DataSketches C++
- 1.0.0-incubating and later · up to and including 5.3.0affected · semver
Same product
apache software foundation: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-123338Apache DataSketches C++: Out-of-bounds write in REQ sketch deserialization allows memory corruption via a crafted sketch0Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Apache Software Foundation Apache DataSketches C++ | 5.3.1 · description | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026same day
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- hataehoonreporter
Not on record for this CVE: EPSS history · variant or chain candidate · public bounty program.
Technical details
No CVSS vector for this record, so attack conditions can't be derived.
Weakness class (CWE)
CWE-787 · Out-of-bounds WriteAttack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log (2)
- Exploit maturity— → none
- Fix✗ → ✓
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References
Show all references (4 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.