TencentOS Server 4: edk2 (TSSA-2026:0116)

high Nessus Plugin ID 300921

Synopsis

The remote TencentOS Server 4 host is missing one or more security updates.

Description

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0116 advisory.

Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

CVE-2026-22796:
Issue summary: A type confusion vulnerability exists in the signature verification of signed PKCS#7 data where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid or NULL pointer dereference when processing malformed PKCS#7 data.

Impact summary: An application performing signature verification of PKCS#7 data or calling directly the PKCS7_digest_from_attributes() function can be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service.

The function PKCS7_digest_from_attributes() accesses the message digest attribute value without validating its type. When the type is not V_ASN1_OCTET_STRING, this results in accessing invalid memory through the ASN1_TYPE union, causing a crash.

Exploiting this vulnerability requires an attacker to provide a malformed signed PKCS#7 to an application that verifies it. The impact of the exploit is just a Denial of Service, the PKCS7 API is legacy and applications should be using the CMS API instead. 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 PKCS#7 parsing implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

CVE-2026-22795:
Issue summary: An invalid or NULL pointer dereference can happen in an application processing a malformed PKCS#12 file.

Impact summary: An application processing a malformed PKCS#12 file can be caused to dereference an invalid or NULL pointer on memory read, resulting in a Denial of Service.

A type confusion vulnerability exists in PKCS#12 parsing code where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid pointer read.

The location is constrained to a 1-byte address space, meaning any attempted pointer manipulation can only target addresses between 0x00 and 0xFF.
This range corresponds to the zero page, which is unmapped on most modern operating systems and will reliably result in a crash, leading only to a Denial of Service. Exploiting this issue also requires a user or application to process a maliciously crafted PKCS#12 file. It is uncommon to accept untrusted PKCS#12 files in applications as they are usually used to store private keys which are trusted by definition. 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 PKCS12 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.

CVE-2025-69421:
Issue summary: Processing a malformed PKCS#12 file can trigger a NULL pointer dereference in the PKCS12_item_decrypt_d2i_ex() function.

Impact summary: A NULL pointer dereference can trigger a crash which leads to Denial of Service for an application processing PKCS#12 files.

The PKCS12_item_decrypt_d2i_ex() function does not check whether the oct parameter is NULL before dereferencing it. When called from PKCS12_unpack_p7encdata() with a malformed PKCS#12 file, this parameter can be NULL, causing a crash. The vulnerability is limited to Denial of Service and cannot be escalated to achieve code execution or memory disclosure.

Exploiting this issue requires an attacker to provide a malformed PKCS#12 file to an application that processes it. 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 PKCS#12 implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

CVE-2025-69420:
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.

CVE-2025-69419:
Issue summary: Calling PKCS12_get_friendlyname() function on a maliciously crafted PKCS#12 file with a BMPString (UTF-16BE) friendly name containing non-ASCII BMP code point can trigger a one byte write before the allocated buffer.

Impact summary: The out-of-bounds write can cause a memory corruption which can have various consequences including a Denial of Service.

The OPENSSL_uni2utf8() function performs a two-pass conversion of a PKCS#12 BMPString (UTF-16BE) to UTF-8. In the second pass, when emitting UTF-8 bytes, the helper function bmp_to_utf8() incorrectly forwards the remaining UTF-16 source byte count as the destination buffer capacity to UTF8_putc(). For BMP code points above U+07FF, UTF-8 requires three bytes, but the forwarded capacity can be just two bytes. UTF8_putc() then returns -1, and this negative value is added to the output length without validation, causing the length to become negative. The subsequent trailing NUL byte is then written at a negative offset, causing write outside of heap allocated buffer.

The vulnerability is reachable via the public PKCS12_get_friendlyname() API when parsing attacker-controlled PKCS#12 files. While PKCS12_parse() uses a different code path that avoids this issue, PKCS12_get_friendlyname() directly invokes the vulnerable function. Exploitation requires an attacker to provide a malicious PKCS#12 file to be parsed by the application and the attacker can just trigger a one zero byte write before the allocated buffer.
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 PKCS#12 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.

CVE-2025-69418:
Issue summary: When using the low-level OCB API directly with AES-NI or other hardware-accelerated code paths, inputs whose length is not a multiple of 16 bytes can leave the final partial block unencrypted and unauthenticated. Impact summary: The trailing 1-15 bytes of a message may be exposed in cleartext on encryption and are not covered by the authentication tag, allowing an attacker to read or tamper with those bytes without detection. The low-level OCB encrypt and decrypt routines in the hardware-accelerated stream path process full 16-byte blocks but do not advance the input/output pointers. The subsequent tail-handling code then operates on the original base pointers, effectively reprocessing the beginning of the buffer while leaving the actual trailing bytes unprocessed. The authentication checksum also excludes the true tail bytes. However, typical OpenSSL consumers using EVP are not affected because the higher-level EVP and provider OCB implementations split inputs so that full blocks and trailing partial blocks are processed in separate calls, avoiding the problematic code path. Additionally, TLS does not use OCB ciphersuites. The vulnerability only affects applications that call the low-level CRYPTO_ocb128_encrypt() or CRYPTO_ocb128_decrypt() functions directly with non-block-aligned lengths in a single call on hardware- accelerated builds. For these reasons the issue was assessed as Low severity. The FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue, as OCB mode is not a FIPS- approved algorithm. 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.

CVE-2025-68160:
Issue summary: Writing large, newline-free data into a BIO chain using the line-buffering filter where the next BIO performs short writes can trigger a heap-based out-of-bounds write.

Impact summary: This out-of-bounds write can cause memory corruption which typically results in a crash, leading to Denial of Service for an application.

The line-buffering BIO filter (BIO_f_linebuffer) is not used by default in TLS/SSL data paths. In OpenSSL command-line applications, it is typically only pushed onto stdout/stderr on VMS systems. Third-party applications that explicitly use this filter with a BIO chain that can short-write and that write large, newline-free data influenced by an attacker would be affected.
However, the circumstances where this could happen are unlikely to be under attacker control, and BIO_f_linebuffer is unlikely to be handling non-curated data controlled by an attacker. For that reason the issue was assessed as Low severity.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the BIO implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

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

Solution

Update the affected packages.

Plugin Details

Severity: High

ID: 300921

File Name: tencentos_TSSA_2026_0116.nasl

Version: 1.1

Type: local

Family: Tencent Local Security Checks

Published: 3/5/2026

Updated: 3/5/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2025-69421

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: p-cpe:/a:tencent:tencentos_server:edk2, cpe:/o:tencent:tencentos_server:4

Required KB Items: Host/local_checks_enabled, Host/etc/os-release, Host/TencentOS/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 3/2/2026

Vulnerability Publication Date: 4/9/2024

Reference Information

CVE: CVE-2025-68160, CVE-2025-69418, CVE-2025-69419, CVE-2025-69420, CVE-2025-69421, CVE-2026-22795, CVE-2026-22796

Detections

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