openssl-src contains Double free after calling PEM_read_bio_ex

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2022-4450: 28.59% estimated exploitation activity in the next 30 days; percentile 98.14 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

The function PEMreadbioex() 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 "nameout", "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 PEMreadbioex() 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 PEMreadbio() and PEMread() are simple wrappers around PEMreadbioex() and therefore these functions are also directly affected. These functions are also…

Published by the source

8 Feb 2023, 22:22 UTC

Last modified by the source

4 Nov 2025, 22:08 UTC

Source last checked

26 Oct 2026, 15:39 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-v5w6-wcm8-jm4q

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# Patch Next advisory brief: CVE-2022-4450

Advisory: openssl-src contains Double free after calling `PEM_read_bio_ex`
IDs: CVE-2022-4450, GHSA-v5w6-wcm8-jm4q
Record: https://patchnext.com/advisories/cve-2022-4450 (revision 1, source checked 26 Oct 2026, 15:39 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: openssl-src 300.0.12, 111.25.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io openssl-src: affected < 111.25.0; >= 300.0.0, < 300.0.12; fixed in 111.25.0, 300.0.12

## Suggested inspection (read-only)
- crates.io openssl-src: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on openssl-src.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-v5w6-wcm8-jm4q (GitHub-reviewed advisory GHSA-v5w6-wcm8-jm4q lists affected ranges: crates.io openssl-src >=0 =300.0.0 <300.0.12)

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