dnsmasq 2.92rel2 RFC 7871 Client Subnet Information information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in dnsmasq 2.92rel2 and classified as problematic. The impacted element is an unknown function of the component RFC 7871 Client Subnet Information Handler. This manipulation causes information disclosure. This vulnerability appears as CVE-2026-4893. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in dnsmasq 2.92rel2. It has been declared as problematic. Affected by this vulnerability is an unknown part of the component RFC 7871 Client Subnet Information Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. The summary by CVE is:

An information disclosure vulnerability in dnsmasq allows remote attackers to bypass source checks via a crafted DNS packet with RFC 7871 client subnet information.

It is possible to read the advisory at kb.cert.org. This vulnerability is known as CVE-2026-4893 since 03/26/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 314983 (Fedora 44 : dnsmasq (2026-ac5cceec13)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (314983), EUVD (EUVD-2026-29155) and CERT Bund (WID-SEC-2026-1468). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source dnsmasq

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 314983
Nessus Name: Fedora 44 : dnsmasq (2026-ac5cceec13)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/26/2026 CVE reserved
05/11/2026 +45 days Advisory disclosed
05/11/2026 +0 days VulDB entry created
07/03/2026 +53 days VulDB entry last update

Sourcesinfo

Advisory: kb.cert.org
Status: Not defined

CVE: CVE-2026-4893 (🔒)
GCVE (CVE): GCVE-0-2026-4893
GCVE (VulDB): GCVE-100-362743
EUVD: 🔒
CERT Bund: WID-SEC-2026-1468 - dnsmasq: Mehrere Schwachstellen

Entryinfo

Created: 05/11/2026 20:41
Updated: 07/03/2026 20:11
Changes: 05/11/2026 20:41 (53), 05/11/2026 22:34 (1), 05/13/2026 07:57 (7), 05/16/2026 11:29 (2), 07/03/2026 20:11 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

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