mutt up to 2.3.1 show_sig_summary null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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2.8$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in mutt up to 2.3.1. Impacted is the function show_sig_summary. The manipulation results in null pointer dereference. This vulnerability was named CVE-2026-43864. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, was found in mutt up to 2.3.1. Affected is the function show_sig_summary. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

mutt before 2.3.2 has a show_sig_summary NULL pointer dereference.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-43864 since 05/04/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 321070 (SUSE SLES12 Security Update : mutt (SUSE-SU-2026:2300-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.3.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321070) and CERT Bund (WID-SEC-2026-1343). Once again VulDB remains the best source for vulnerability data.

Affected

  • Open Source mutt

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.8
VulDB Meta Temp Score: 2.8

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 2.5
CNA Vector (MITRE): 🔒

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 321070
Nessus Name: SUSE SLES12 Security Update : mutt (SUSE-SU-2026:2300-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mutt 2.3.2

Timelineinfo

05/04/2026 Advisory disclosed
05/04/2026 +0 days CVE reserved
05/04/2026 +0 days VulDB entry created
06/14/2026 +41 days VulDB entry last update

Sourcesinfo

Advisory: ebfa2969042d89303d15334193fcc32866c8a8df
Status: Confirmed

CVE: CVE-2026-43864 (🔒)
GCVE (CVE): GCVE-0-2026-43864
GCVE (VulDB): GCVE-100-360948
CERT Bund: WID-SEC-2026-1343 - mutt: Mehrere Schwachstellen

Entryinfo

Created: 05/04/2026 09:21
Updated: 06/14/2026 21:39
Changes: 05/04/2026 09:21 (65), 05/04/2026 12:54 (7), 06/14/2026 21:39 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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