CVE-2023-49083

cryptography vulnerable to NULL-dereference when loading PKCS7 certificates

HIGH
7.5
CVSS Score
Published: November 29, 2023 at 06:50 PM UTC
Updated: June 17, 2026 at 06:35 AM UTC
2 products affected across 2 vendorsCryptographyCryptography

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Severity
HIGH7.5
Exploit prediction
EPSS 1.0%
SSVC
PoC

Description

cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Calling `load_pem_pkcs7_certificates` or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference and segfault. Exploitation of this vulnerability poses a serious risk of Denial of Service (DoS) for any application attempting to deserialize a PKCS7 blob/certificate. The consequences extend to potential disruptions in system availability and stability. This vulnerability has been patched in version 41.0.6.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.1 ≤ v < 41.0.6
Affected range stops below 41.0.6, so it looks safe — our inference, not a vendor statement
v < 41.0.6
Affected range stops below 41.0.6, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-476

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