OpenSSL up to 3.6.0 TimeStamp Response Verification TS_RESP_verify_response unusual condition

Summaryinfo

A vulnerability has been found in OpenSSL up to 3.6.0 and classified as problematic. The impacted element is the function TS_RESP_verify_response of the component TimeStamp Response Verification. The manipulation leads to unusual condition. This vulnerability is documented as CVE-2025-69420. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OpenSSL up to 3.6.0 and classified as problematic. This issue affects the function TS_RESP_verify_response of the component TimeStamp Response Verification. The manipulation with an unknown input leads to a unusual condition vulnerability. Using CWE to declare the problem leads to CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. Impacted is availability. The summary by CVE is:

Issue summary: A type confusion vulnerability exists in the TimeStamp Response verification code where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid or NULL pointer dereference when processing a malformed TimeStamp Response file. Impact summary: An application calling TS_RESP_verify_response() with a malformed TimeStamp Response can be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service. The functions ossl_ess_get_signing_cert() and ossl_ess_get_signing_cert_v2() access the signing cert attribute value without validating its type. When the type is not V_ASN1_SEQUENCE, this results in accessing invalid memory through the ASN1_TYPE union, causing a crash. Exploiting this vulnerability requires an attacker to provide a malformed TimeStamp Response to an application that verifies timestamp responses. The TimeStamp protocol (RFC 3161) is not widely used and the impact of the exploit is just a Denial of Service. For these reasons the issue was assessed as Low severity. The FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the TimeStamp Response implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0 and 1.1.1 are vulnerable to this issue. OpenSSL 1.0.2 is not affected by this issue.

It is possible to read the advisory at openssl-library.org. The identification of this vulnerability is CVE-2025-69420 since 01/06/2026. 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 of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/13/2026).

The vulnerability scanner Nessus provides a plugin with the ID 296784 (OpenSSL 3.3.0 < 3.3.6 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.1.1ze, 3.0.19, 3.3.6, 3.4.4, 3.5.5 or 3.6.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (296784) and CERT Bund (WID-SEC-2026-0234). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• IBM VIOS
• IBM AIX
• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• NetApp Data ONTAP
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IGEL OS
• SUSE openSUSE
• Fabasoft Cloud
• RESF Rocky Linux
• IBM App Connect Enterprise
• Open Source OpenSSL
• Broadcom Brocade SANnav
• Fortinet FortiPortal
• Meinberg LANTIME
• Red Hat OpenShift
• IBM MQ
• Open Source Camunda
• ABB AC-500

Productinfo

Type

• Network Encryption Software

Name

• OpenSSL

Version

• 1.1.1za
• 1.1.1zb
• 1.1.1zc
• 1.1.1zd
• 3.0
• 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
• 3.1
• 3.2
• 3.3
• 3.3.0
• 3.3.1
• 3.3.2
• 3.3.3
• 3.3.4
• 3.3.5
• 3.4
• 3.4.0
• 3.4.1
• 3.4.2
• 3.4.3
• 3.5
• 3.5.0
• 3.5.1
• 3.5.2
• 3.5.3
• 3.5.4
• 3.6.0

License

• open-source

Website

• Product: https://www.openssl.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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

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