Critical severity · published Apr 8, 2026
CVE-2026-39892
cryptography has a buffer overflow if non-contiguous buffers were passed to APIs
9.8
CVSS
0.7%
EPSS
No
On KEV
Description
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. From 45.0.0 to before 46.0.7, if a non-contiguous buffer was passed to APIs which accepted Python buffers (e.g. Hash.update()), this could lead to buffer overflows. This vulnerability is fixed in 46.0.7.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CR
cryptography · pyca
>= 45.0.0, < 46.0.7 · source: vendor, NVD
LC
Lightspeed Core · Red Hat
All versions, or not specified · source: CISA
MT
Migration Toolkit for Applications 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server 3.3 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform Ansible Core 2 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Discovery 2 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-39892
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-39892
Vendor Advisory
https://github.com/pyca/cryptography/security/advisories/GHSA-p423-j2cm-9vmq
Mailing List
http://www.openwall.com/lists/oss-security/2026/04/08/12
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:19375
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:20338
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:21017
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:22465
More from cryptography
8.7
CVE-2026-69249
python-cryptography: Duplicate self-signed intermediates can cause exponential path-building
8.2
CVE-2026-69247
cryptography: PKCS#7 EnvelopedData decryption exposes a Bleichenbacher oracle through distinguishable errors and timing
6.9
CVE-2026-69248
python-cryptography verifier accepts wildcard DNS names allowing escape from permittedSubtrees
5.3
CVE-2026-34073
cryptography has incomplete DNS name constraint enforcement on peer names