CVE-2026-103501
Apache DataSketches: datasketches-cpp: HLL CouponList Deserialization Buffer Overflow allows memory corruption via a crafted sketch
- State
- Published
- Severity
- 9.8 Critical
- Published
- Oct 10, 2026
- Updated
- Oct 16, 2026
- Reserved
- Sep 30, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CISA-ADP |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
Apache DataSketchesApache Software Foundation |
|
References
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