obgm libcoap 4.3.5 X.509 Certificate src/coap_openssl.c get_san_or_cn_from_cert null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in obgm libcoap 4.3.5. Affected by this vulnerability is the function get_san_or_cn_from_cert of the file src/coap_openssl.c of the component X.509 Certificate Handler. The manipulation leads to null pointer dereference. This vulnerability is uniquely identified as CVE-2025-65494. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in obgm libcoap 4.3.5. It has been rated as problematic. This issue affects the function get_san_or_cn_from_cert of the file src/coap_openssl.c of the component X.509 Certificate Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability. The summary by CVE is:

NULL pointer dereference in get_san_or_cn_from_cert() in src/coap_openssl.c in OISM libcoap 4.3.5 allows remote attackers to cause a denial of service via a crafted X.509 certificate that causes sk_GENERAL_NAME_value() to return NULL.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2025-65494 since 11/18/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 276684 (Linux Distros Unpatched Vulnerability : CVE-2025-65494), 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 vulnerability database at Tenable (276684). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
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: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 276684
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-65494

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/18/2025 CVE reserved
11/24/2025 +6 days Advisory disclosed
11/24/2025 +0 days VulDB entry created
11/25/2025 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Not defined

CVE: CVE-2025-65494 (🔒)
GCVE (CVE): GCVE-0-2025-65494
GCVE (VulDB): GCVE-100-333377

Entryinfo

Created: 11/24/2025 16:08
Updated: 11/25/2025 13:23
Changes: 11/24/2025 16:08 (55), 11/25/2025 13:23 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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