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CVE-2026-103513NVD status: Awaiting Analysis

Apache DataSketches: Out-of-bounds Read

CVE-2026-103513 is a critical-severity out-of-bounds read vulnerability in Apache DataSketches from Apache, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Apache DataSketches versions: 2.0.0-incubating through 5.2.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.39% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Apache DataSketches you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache DataSketches2.0.0-incubating through 5.2.0Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

Out-of-bounds read and write in the CPC sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp). A crafted serialized CPC sketch passed to cpc_sketch::deserialize(), from either a byte buffer or a stream, can cause the decompressor to read past the end of the compressed data, because the read position was only checked after decoding finished. In the hybrid flavor, it can also cause a write outside an internal heap buffer, because decoded row indices were not validated. Several other header fields and decoded values, including lg_k, were also not validated. This can corrupt heap memory, causing a crash and potentially enabling further exploitation. This issue affects Apache DataSketches C++: from 2.0.0-incubating before 5.3.0. Only applications that deserialize CPC sketches from untrusted sources are affected. Users are recommended to upgrade to version 5.3.0, which fixes this issue.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Apache DataSketches

All Apache DataSketches vulnerabilities

Recent Out-of-bounds Read vulnerabilities

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