GnuPG up to 2.5.16 Signature Packet Length parse_signature null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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4.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in GnuPG up to 2.5.16. This issue affects the function parse_signature of the component Signature Packet Length Handler. Executing a manipulation can lead to null pointer dereference. This vulnerability is tracked as CVE-2026-24883. The attack can be launched remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in GnuPG up to 2.5.16. This vulnerability affects the function parse_signature of the component Signature Packet Length Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect availability. CVE summarizes:

In GnuPG before 2.5.17, a long signature packet length causes parse_signature to return success with sig->data[] set to a NULL value, leading to a denial of service (application crash).

The advisory is shared for download at openwall.com. This vulnerability was named CVE-2026-24883 since 01/27/2026. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 296934 (Linux Distros Unpatched Vulnerability : CVE-2026-24883), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.5.17 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (296934) and CERT Bund (WID-SEC-2026-0231). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Fedora Linux
  • SUSE Linux
  • Open Source GnuPG
  • Open Source Gpg4win

Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.3

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CNA Base Score: 3.7
CNA Vector (MITRE): 🔒

CVSSv2info

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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: 296934
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-24883

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: GnuPG 2.5.17

Timelineinfo

01/27/2026 Advisory disclosed
01/27/2026 +0 days CVE reserved
01/27/2026 +0 days VulDB entry created
02/07/2026 +11 days VulDB entry last update

Sourcesinfo

Advisory: openwall.com
Status: Confirmed

CVE: CVE-2026-24883 (🔒)
GCVE (CVE): GCVE-0-2026-24883
GCVE (VulDB): GCVE-100-343072
CERT Bund: WID-SEC-2026-0231 - GnuPG und Gpg4win: Mehrere Schwachstellen

Entryinfo

Created: 01/27/2026 20:46
Updated: 02/07/2026 03:43
Changes: 01/27/2026 20:46 (64), 01/28/2026 13:04 (2), 01/28/2026 22:47 (7), 02/03/2026 10:36 (1), 02/03/2026 14:09 (1), 02/07/2026 03:43 (11)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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