How severe is CVE-2024-0727?

CVE-2024-0727 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2024-0727?

CVE-2024-0727 affects the following packages: cryptography (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2024-0727?

Update cryptography to 42.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-0727 is resolved across your whole dependency graph.

How do I detect CVE-2024-0727 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cryptography, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2024-0727 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2024-0727 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-0727 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2024-0727?

CVE-2024-0727 has an EPSS (Exploit Prediction Scoring System) score of 3.2%, placing it in the 88th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2024-0727?

CVE-2024-0727 is classified as NULL Pointer Dereference (CWE-476). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2024-0727 published, and has it been updated?

CVE-2024-0727 was published on January 26, 2024 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

MEDIUM severity

CVE-2024-0727 — cryptography

MEDIUMFix: openssl/openssl@09df439

CVE-2024-0727 is a medium-severity (CVSS 5.5) NULL Pointer Dereference vulnerability in cryptography. A fix is available for cryptography — see the affected versions and patch details below.

PKCS12 Decoding crashes

Also known asGHSA-9v9h-cgj8-h64pPYSEC-2026-1285

Published

Jan 26, 2024

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2024-0727.

EPSS Exploitation Probability

via FIRST.org ↗

3.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs88th percentile — riskier than 88% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍cryptography

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Issue summary: Processing a maliciously formatted PKCS12 file may lead OpenSSL to crash leading to a potential Denial of Service attack

Impact summary: Applications loading files in the PKCS12 format from untrusted sources might terminate abruptly.

A file in PKCS12 format can contain certificates and keys and may come from an untrusted source. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly check for this case. This can lead to a NULL pointer dereference that results in OpenSSL crashing. If an application processes PKCS12 files from an untrusted source using the OpenSSL APIs then that application will be vulnerable to this issue.

OpenSSL APIs that are vulnerable to this are: PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes() and PKCS12_newpass().

We have also fixed a similar issue in SMIME_write_PKCS7(). However since this function is related to writing data we do not consider it security significant.

The FIPS modules in 3.2, 3.1 and 3.0 are not affected by this issue.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`cryptography`	all versions	42.0.2`pip install --upgrade 'cryptography==42.0.2'`

Affected Products

1 product · 5 configurations

Application

opensslopenssl

≥ 3.1.0 && < 3.1.5

1 version

3.2.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cryptography, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update cryptography to 42.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-0727 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatLow

This vulnerability is classified as low severity. This is a result of a lack of proper validation in OpenSSL's handling of PKCS12 files. This vulnerability results in a potential Denial of Service scenario wherein maliciously crafted PKCS12 files may cause OpenSSL to crash due to a NULL pointer dereference. However,…

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Source: Red Hat security advisory for CVE-2024-0727 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Enterprise Linux 9	`openssl-1:3.0.7-27.el9`	RHSA-2024:2447
Red Hat Enterprise Linux 9	`edk2-0:20240524-6.el9_5`	RHSA-2024:9088

Frequently Asked Questions

Issue summary: Processing a maliciously formatted PKCS12 file may lead OpenSSL to crash leading to a potential Denial of Service attack Impact summary: Applications loading files in the PKCS12 format from untrusted sources might terminate abruptly. A file in PKCS12 format can contain certificates and keys and may come from an untrusted source. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly check for this case. This can lead to a NULL pointer dereference that results in OpenSSL crashing. If an application processes PKCS12 files from an untrusted sour

O3 Security · Impact-Aware SCA

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