CVE-2022-4450
The function PEM_read_bio_ex() reads a PEM file from a BIO and parses and decodes the "name" (e.g. "CERTIFICATE"), any header data and the payload data. If the function succeeds then the "name_out", "header" and "data" arguments are populated with pointers to buffers containing the relevant decoded data. The caller is responsible for freeing those buffers. It is possible to construct a PEM file that results in 0 bytes of payload data. In this case PEM_read_bio_ex() will return a failure code but will populate the header argument with a pointer to a buffer that has already been freed. If the caller also frees this buffer then a double free will occur. This will most likely lead to a crash. This could be exploited by an attacker who has the ability to supply malicious PEM files for parsing to achieve a denial of service attack.
The functions PEM_read_bio() and PEM_read() are simple wrappers around PEM_read_bio_ex() and therefore these functions are also directly affected.
These functions are also called indirectly by a number of other OpenSSL functions including PEM_X509_INFO_read_bio_ex() and SSL_CTX_use_serverinfo_file() which are also vulnerable. Some OpenSSL internal uses of these functions are not vulnerable because the caller does not free the header argument if PEM_read_bio_ex() returns a failure code. These locations include the PEM_read_bio_TYPE() functions as well as the decoders introduced in OpenSSL 3.0.
The OpenSSL asn1parse command line application is also impacted by this issue.
| Software | From | Fixed in |
|---|---|---|
| openssl / openssl | 3.0.0 | 3.0.8 |
| openssl / openssl | 1.1.1 | 1.1.1t |
openssl-src
|
- | 111.25.0 |
|
openssl-src
|
300.0.0 | 300.0.12 |
| stormshield / stormshield_network_security | 4.4.0 | 4.6.3 |
| stormshield / stormshield_network_security | 4.0.0 | 4.3.16 |
- https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=63bcf189be73a9cc1264059bed6f57974be74a83
- https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=bbcf509bd046b34cca19c766bbddc31683d0858b
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0003
- https://rustsec.org/advisories/RUSTSEC-2023-0010.html
- https://security.gentoo.org/glsa/202402-08
- https://www.openssl.org/news/secadv/20230207.txt
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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.
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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.
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