CVE-2026-42371

Application crash via truncated range lengths

Published Apr 27, 2026 · Updated Apr 27, 2026

Numeric truncation in uriparser before 1.0.1 allows local users to crash a consuming application with a multi-gigabyte URI. CompareRange casts pointer-difference lengths to int, so 64-bit values can truncate and unequal ranges can be treated as equal before content comparison. Reachability requires a 64-bit consumer that accepts a URI several gigabytes long; exploitation interrupts that consumer rather than exposing or changing data.

CVSS severity5.1
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Numeric truncation in uriparser before 1.0.1 allows local users to crash a consuming application with a multi-gigabyte URI. CompareRange casts pointer-difference lengths to int, so 64-bit values can truncate and unequal ranges can be treated as equal before content comparison. Reachability requires a 64-bit consumer that accepts a URI several gigabytes long; exploitation interrupts that consumer rather than exposing or changing data.

The record

CVE
CVE-2026-42371
Published
Apr 27, 2026
Updated
Apr 27, 2026
Vendor
uriparser project
Product
uriparser
Classifications
CWE-197, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.0.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

uriparser project · uriparserversion=0 <1.0.1

Published CVSS scores

5.1MITRECVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-197Numeric Truncation Error
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo