OpenSSL 1.0.2 < 1.0.2zp Multiple Vulnerabilities

high Nessus Plugin ID 305203

Synopsis

The remote service is affected by multiple vulnerabilities.

Description

The version of OpenSSL installed on the remote host is prior to 1.0.2zp. It is, therefore, affected by multiple vulnerabilities as referenced in the 1.0.2zp advisory.

- Issue summary: During processing of a crafted CMS EnvelopedData message with KeyTransportRecipientInfo a NULL pointer dereference can happen. Impact summary: Applications that process attacker-controlled CMS data may crash before authentication or cryptographic operations occur resulting in Denial of Service.
When a CMS EnvelopedData message that uses KeyTransportRecipientInfo with RSA-OAEP encryption is processed, the optional parameters field of RSA-OAEP SourceFunc algorithm identifier is examined without checking for its presence. This results in a NULL pointer dereference if the field is missing.
Applications and services that call CMS_decrypt() on untrusted input (e.g., S/MIME processing or CMS-based protocols) are vulnerable. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary. Fixed in OpenSSL 1.1.1zg (Affected since 1.1.1). (CVE-2026-28390)

- Issue summary: During processing of a crafted CMS EnvelopedData message with KeyAgreeRecipientInfo a NULL pointer dereference can happen. Impact summary: Applications that process attacker-controlled CMS data may crash before authentication or cryptographic operations occur resulting in Denial of Service. When a CMS EnvelopedData message that uses KeyAgreeRecipientInfo is processed, the optional parameters field of KeyEncryptionAlgorithmIdentifier is examined without checking for its presence. This results in a NULL pointer dereference if the field is missing. Applications and services that call CMS_decrypt() on untrusted input (e.g., S/MIME processing or CMS-based protocols) are vulnerable. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary. Fixed in OpenSSL 1.1.1zg (Affected since 1.1.1). (CVE-2026-28389)

- Issue summary: When a delta CRL that contains a Delta CRL Indicator extension is processed a NULL pointer dereference might happen if the required CRL Number extension is missing. Impact summary: A NULL pointer dereference can trigger a crash which leads to a Denial of Service for an application. When CRL processing and delta CRL processing is enabled during X.509 certificate verification, the delta CRL processing does not check whether the CRL Number extension is NULL before dereferencing it. When a malformed delta CRL file is being processed, this parameter can be NULL, causing a NULL pointer dereference. Exploiting this issue requires the X509_V_FLAG_USE_DELTAS flag to be enabled in the verification context, the certificate being verified to contain a freshestCRL extension or the base CRL to have the EXFLAG_FRESHEST flag set, and an attacker to provide a malformed CRL to an application that processes it. The vulnerability is limited to Denial of Service and cannot be escalated to achieve code execution or memory disclosure. For that reason the issue was assessed as Low severity according to our Security Policy. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary. Fixed in OpenSSL 1.1.1zg (Affected since 1.1.1). (CVE-2026-28388)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Upgrade to OpenSSL version 1.0.2zp or later.

See Also

https://openssl-library.org/news/secadv/20260407.txt

http://www.nessus.org/u?eac4598c

https://www.cve.org/CVERecord?id=CVE-2026-28388

https://www.cve.org/CVERecord?id=CVE-2026-28389

https://www.cve.org/CVERecord?id=CVE-2026-28390

Plugin Details

Severity: High

ID: 305203

File Name: openssl_1_0_2zp.nasl

Version: 1.1

Type: Combined

Agent: windows, macosx, unix

Family: Web Servers

Published: 4/7/2026

Updated: 4/7/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2026-28390

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:openssl:openssl

Required KB Items: installed_sw/OpenSSL

Exploit Ease: No known exploits are available

Patch Publication Date: 4/7/2026

Vulnerability Publication Date: 4/7/2026

Reference Information

CVE: CVE-2026-28388, CVE-2026-28389, CVE-2026-28390