Vulnerability Database

328,409

Total vulnerabilities in the database

CVE-2021-3711

In order to decrypt SM2 encrypted data an application is expected to call the API function EVP_PKEY_decrypt(). Typically an application will call this function twice. The first time, on entry, the "out" parameter can be NULL and, on exit, the "outlen" parameter is populated with the buffer size required to hold the decrypted plaintext. The application can then allocate a sufficiently sized buffer and call EVP_PKEY_decrypt() again, but this time passing a non-NULL value for the "out" parameter. A bug in the implementation of the SM2 decryption code means that the calculation of the buffer size required to hold the plaintext returned by the first call to EVP_PKEY_decrypt() can be smaller than the actual size required by the second call. This can lead to a buffer overflow when EVP_PKEY_decrypt() is called by the application a second time with a buffer that is too small. A malicious attacker who is able present SM2 content for decryption to an application could cause attacker chosen data to overflow the buffer by up to a maximum of 62 bytes altering the contents of other data held after the buffer, possibly changing application behaviour or causing the application to crash. The location of the buffer is application dependent but is typically heap allocated. Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k).

CVSS v3:

  • Severity: Critical
  • Score: 9.8
  • AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2:

  • Severity: High
  • Score: 7.5
  • AV:N/AC:L/Au:N/C:P/I:P/A:P

CWEs:

Software From Fixed in
openssl / openssl 1.1.1 1.1.1l
debian / debian_linux 10.0 10.0.x
debian / debian_linux 11.0 11.0.x
netapp / e-series_santricity_os_controller 11.0 11.50.2.x
oracle / peoplesoft_enterprise_peopletools 8.57 8.57.x
oracle / jd_edwards_world_security a9.4 a9.4.x
oracle / peoplesoft_enterprise_peopletools 8.58 8.58.x
oracle / enterprise_session_border_controller 8.4 8.4.x
oracle / enterprise_communications_broker 3.2.0 3.2.0.x
oracle / zfs_storage_appliance_kit 8.8 8.8.x
oracle / peoplesoft_enterprise_peopletools 8.59 8.59.x
oracle / mysql_server 8.0.0 8.0.26.x
oracle / communications_session_border_controller 8.4 8.4.x
oracle / enterprise_session_border_controller 9.0 9.0.x
oracle / communications_session_border_controller 9.0 9.0.x
oracle / mysql_server 5.7.0 5.7.35.x
oracle / communications_cloud_native_core_security_edge_protection_proxy 1.7.0 1.7.0.x
oracle / mysql_enterprise_monitor - 8.0.25.x
oracle / enterprise_communications_broker 3.3.0 3.3.0.x
oracle / essbase - 11.1.2.4.47
oracle / mysql_connectors - 8.0.27.x
oracle / essbase 21.1 21.3
oracle / communications_unified_session_manager 8.2.5 8.2.5.x
oracle / communications_cloud_native_core_unified_data_repository 1.15.0 1.15.0.x
oracle / health_sciences_inform_publisher 6.3.1.1 6.3.1.1.x
oracle / health_sciences_inform_publisher 6.2.1.1 6.2.1.1.x
oracle / jd_edwards_enterpriseone_tools - 9.2.6.3
oracle / communications_unified_session_manager 8.4.5 8.4.5.x
tenable / tenable.sc 5.16.0 5.19.1.x
tenable / nessus_network_monitor - 5.13.1.x
Rust icon openssl-src - 111.16.0

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.