Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-103636— Apache DataSketches: datasketches-cpp: Out-of-bounds read in VarOpt union deserialization allows denial of service via a truncated sketch

Quick assessment

Affected
Apache Software Foundation Apache DataSketches
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

以下是漏洞描述信息的中文翻译： Apache DataSketches C++（仓库地址：datasketches-cpp）中的 VarOpt 联合反序列化存在越界读取漏洞。 在 函数中，代码在仅检查到剩余 8 字节可用空间的情况下，仍会读取非空联合对象头部的 32 字节前导数据。因此，经过截断的反序列化联合对象可能导致最多超出输入末尾 24 字节的越界读取。对于此类输入，嵌入式 sketch（草图）的剩余大小是通过无符号减法计算的，可能导致数值回绕（wrap around），从而使嵌入式 sketch 自身的边界

AI Predicted 7.5 Difficulty: Moderate EPSS 0.24% · P14

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution

Affected Version Matrix 1

VendorProduct Version RangeStatus
Apache Software Foundation Apache DataSketches 2.0.0-incubating≤ 5.2.0 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-103636

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Apache DataSketches: datasketches-cpp: Out-of-bounds read in VarOpt union deserialization allows denial of service via a truncated sketch
Source: CVE Program / CVE List V5
Vulnerability Description
Out-of-bounds read in the VarOpt union deserialization of Apache DataSketches C++ (repo: datasketches-cpp). var_opt_union::deserialize() read the 32-byte preamble of a non-empty union after checking that only 8 bytes were available, so a truncated serialized union could cause a read of up to 24 bytes past the end of the input. For such inputs, the size remaining for the embedded sketch was also computed by an unsigned subtraction that could wrap around, so the embedded sketch's own size checks no longer limited reads to the input. The bytes read can become part of the deserialized union's state. This can cause a crash (denial of service) and could expose adjacent memory contents. This issue affects Apache DataSketches C++: from 2.0.0-incubating before 5.3.0. Only applications that deserialize VarOpt unions from untrusted sources are affected. Users are recommended to upgrade to version 5.3.0, which fixes this issue.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
跨界内存读
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Apache Software Foundation Apache DataSketches 2.0.0-incubating ~ 5.2.0 -

II. Public POCs for CVE-2026-103636

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-103636

请登录查看更多情报信息。

Mailing List Discussions for CVE-2026-103636 (1)

Vendor Pages for CVE-2026-103636 (1)

Same Patch Batch · Apache Software Foundation · 2026-10-10 · 4 CVEs total

CVE-2026-103635 Apache DataSketches: datasketches-cpp: Out-of-bounds read in compact Theta sketch deserial
CVE-2026-103513 Apache DataSketches: datasketches-cpp: Out-of-bounds read and write in the CPC sketch dese
CVE-2026-103501 Apache DataSketches: datasketches-cpp: HLL CouponList Deserialization Buffer Overflow allo

IV. Related Vulnerabilities

Same product: Apache DataSketches
Same vendor: Apache Software Foundation
Same weakness: CWE-125

V. Comments for CVE-2026-103636

No comments yet

Leave a comment