CVE-2024-26130 is a high-severity (CVSS 7.5) NULL Pointer Dereference vulnerability in cryptography. A fix is available for cryptography — see the affected versions and patch details below.
cryptography NULL pointer deference with pkcs12.serialize_key_and_certificates when called with a non-matching certificate and private key and an hmac_hash override
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2024-26130.
EPSS Exploitation Probability
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
cryptographyReal-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
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Starting in version 38.0.0 and prior to version 42.0.4, if pkcs12.serialize_key_and_certificates is called with both a certificate whose public key did not match the provided private key and an encryption_algorithm with hmac_hash set (via PrivateFormat.PKCS12.encryption_builder().hmac_hash(...), then a NULL pointer dereference would occur, crashing the Python process. This has been resolved in version 42.0.4, the first version in which a ValueError is properly raised.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | cryptography | ≥ 38.0.0&&< 42.0.4 | 42.0.4pip install --upgrade 'cryptography==42.0.4' |
Affected Products
cryptographycryptography.ioDetection & mitigation playbook
Open-source dependencyDetect
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 42.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-26130 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
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.
The vulnerability in python-cryptography that leads to a NULL pointer dereference during the pkcs12.serialize_key_and_certificates function execution is classified as a moderate severity issue. While the vulnerability can result in a denial-of-service (DoS) by crashing the Python process, it requires specific…
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-2024-26130 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Automation Platform 2.4 for RHEL 8 | python3x-cryptography-0:42.0.5-1.el8ap | RHSA-2024:3781 |
| Red Hat Enterprise Linux 9 | python3.12-cryptography-0:41.0.7-2.el9_6.1 | RHSA-2025:15608 |
| Red Hat Satellite 6.15 for RHEL 8 | python-cryptography-0:42.0.8-1.el8pc | RHSA-2024:7987 |
| RHUI 4 for RHEL 8 | python-cryptography-0:42.0.8-1.el8ui | RHSA-2025:1335 |
Frequently Asked Questions
Is CVE-2024-26130 in your dependencies?
Find it across PyPI, including transitive dependencies.