CVE-2026-123338: Apache DataSketches C++ · Out-of-bounds Write Vulnerability
Source GCVE Database
Not known to be exploited · fixed in 5.3.1 : patch Apache DataSketches C++ soon.
Data as of 13 Nov 2026, 13:18 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in 5.3.1
Exploitation evidence
Disclosed: evidence found.
CVE published 13 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Apache DataSketches C++apache/datasketches-cpp | Affected
| Fixed in– |
GitHubapache/datasketches-cpppkg:github/apache/datasketches-cppOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should upgrade Apache DataSketches C++ to version 5.3.1, which contains the fix for this vulnerability.
Description
An out-of-bounds write vulnerability exists in Apache DataSketches C++ versions 3.0.0 through 5.3.0. This flaw occurs when an application deserializes a REQ sketch from an untrusted source without validating the serialized compactor headers, potentially leading to heap memory corruption. The issue is fixed in version 5.3.1.
References
- nvd.nist.gov/vuln/detail/CVE-2026-123338 (opens in a new tab)
- github.com/apache/datasketches-cpp/pull/568 (opens in a new tab)
- github.com/apache/datasketches-cpp/commit/9839ffd2ccc038d453e38b545750a5ed2d589dea (opens in a new tab)
- github.com/apache/datasketches-cpp/releases/tag/5.3.1 (opens in a new tab)
- lists.apache.org/thread/wjsso4wl0f0nczwh7gd74kc5wckn1635 (opens in a new tab)
- openwall.com/lists/oss-security/2026/11/13/2 (opens in a new tab)