OpenSSL up to 3.6.1 Delta CRL null pointer dereference

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.1	$0-$5k	0.29

Summaryinfo

A vulnerability labeled as problematic has been found in OpenSSL up to 3.6.1. Affected is an unknown function of the component Delta CRL Handler. Such manipulation leads to null pointer dereference. This vulnerability is traded as CVE-2026-28388. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OpenSSL up to 3.6.1. It has been rated as problematic. Affected by this issue is an unknown part of the component Delta CRL 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 weakness was shared by Igor Morgenstern. The advisory is shared for download at openssl-library.org. This vulnerability is handled as CVE-2026-28388. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/09/2026).

The vulnerability scanner Nessus provides a plugin with the ID 305682 (SUSE SLES15 Security Update : openssl-3 (SUSE-SU-2026:1213-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.0.2zp, 1.1.1zg, 3.0.20, 3.3.7, 3.4.5, 3.5.6 or 3.6.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (305682) and EUVD (EUVD-2026-19962). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Network Encryption Software

Name

• OpenSSL

Version

• 1.0.2za
• 1.0.2zb
• 1.0.2zc
• 1.0.2zd
• 1.0.2ze
• 1.0.2zf
• 1.0.2zg
• 1.0.2zh
• 1.0.2zi
• 1.0.2zj
• 1.0.2zk
• 1.0.2zl
• 1.0.2zm
• 1.0.2zn
• 1.0.2zo
• 1.1.1za
• 1.1.1zb
• 1.1.1zc
• 1.1.1zd
• 1.1.1ze
• 1.1.1zf
• 3.0.0
• 3.0.1
• 3.0.2
• 3.0.3
• 3.0.4
• 3.0.5
• 3.0.6
• 3.0.7
• 3.0.8
• 3.0.9
• 3.0.10
• 3.0.11
• 3.0.12
• 3.0.13
• 3.0.14
• 3.0.15
• 3.0.16
• 3.0.17
• 3.0.18
• 3.0.19
• 3.3.0
• 3.3.1
• 3.3.2
• 3.3.3
• 3.3.4
• 3.3.5
• 3.3.6
• 3.4.0
• 3.4.1
• 3.4.2
• 3.4.3
• 3.4.4
• 3.5.0
• 3.5.1
• 3.5.2
• 3.5.3
• 3.5.4
• 3.5.5
• 3.6.0
• 3.6.1

License

• open-source

Website

• Product: https://www.openssl.org/

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

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 305682
Nessus Name: SUSE SLES15 Security Update : openssl-3 (SUSE-SU-2026:1213-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: OpenSSL 1.0.2zp/1.1.1zg/3.0.20/3.3.7/3.4.5/3.5.6/3.6.2

Timelineinfo

04/07/2026 Advisory disclosed
04/07/2026 +0 days VulDB entry created
04/09/2026 +2 days VulDB entry last update

Sourcesinfo

Product: openssl.org

Advisory: openssl-library.org
Researcher: Igor Morgenstern
Status: Confirmed

CVE: CVE-2026-28388 (🔒)
GCVE (CVE): GCVE-0-2026-28388
GCVE (VulDB): GCVE-100-355904
EUVD: 🔒

Entryinfo

Created: 04/07/2026 21:14
Updated: 04/09/2026 15:56
Changes: 04/07/2026 21:14 (53), 04/08/2026 02:32 (1), 04/09/2026 15:56 (2)
Complete: 🔍
Cache ID: 216:239:103

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

Discussion

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