CVE-2025-24294Network attack vector

Application thread hang via oversized DNS name decompression

Published Jul 12, 2025 · Updated Jul 16, 2025

Denial of service in Ruby Resolv 0.2.2 and earlier, 0.3.0, and 0.6.1 and earlier allows remote attackers to hang application threads. Resolv::DNS::Message.decode calls get_labels, which follows compressed-name pointers and appends labels without enforcing DNS's 255-octet name limit. Reachability requires an application to parse an attacker-influenced DNS response; successful exploitation consumes CPU and leaves that application thread unresponsive.

CVSS severity7.5
High
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Ruby Resolv 0.2.2 and earlier, 0.3.0, and 0.6.1 and earlier allows remote attackers to hang application threads. Resolv::DNS::Message.decode calls get_labels, which follows compressed-name pointers and appends labels without enforcing DNS's 255-octet name limit. Reachability requires an application to parse an attacker-influenced DNS response; successful exploitation consumes CPU and leaves that application thread unresponsive.

The record

CVE
CVE-2025-24294
Published
Jul 12, 2025
Updated
Jul 16, 2025
Vendor
libwww-perl
Product
Resolv
Classifications
CWE-1284, CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 16, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=0.2 <=0.2.2
  2. Affected versionversion=0.3.0 <=0.3.0
  3. Affected versionversion=0.6 <=0.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

libwww-perl · Resolvversion=0.2 <=0.2.2; version=0.3.0 <=0.3.0; version=0.6 <=0.6.1

Published CVSS scores

7.5CISA ADPCVSS:3.1/AV:N/AC:L/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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1284Improper Validation of Specified Quantity in Input
CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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