CVE-2023-0401Network attack vector

Application crash via unchecked digest initialization

Published Feb 8, 2023 · Updated Nov 4, 2025

NULL pointer dereference in PKCS7 verification in OpenSSL 3.0.0 through 3.0.7 allows attackers to crash consuming applications. The signature-verification path fails to check unsuccessful digest initialization when a recognized hash implementation is unavailable, then misuses the digest API. Exposure requires an application to verify attacker-controlled PKCS7 signed or signedAndEnveloped data through SMIME or time-stamp APIs; OpenSSL TLS does not reach this path.

CVSS severity7.5
High
EPSS probability1.85%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in PKCS7 verification in OpenSSL 3.0.0 through 3.0.7 allows attackers to crash consuming applications. The signature-verification path fails to check unsuccessful digest initialization when a recognized hash implementation is unavailable, then misuses the digest API. Exposure requires an application to verify attacker-controlled PKCS7 signed or signedAndEnveloped data through SMIME or time-stamp APIs; OpenSSL TLS does not reach this path.

The record

CVE
CVE-2023-0401
Published
Feb 8, 2023
Updated
Nov 4, 2025
Vendor
OpenSSL Project
Product
OpenSSL
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 8, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.0.0 <3.0.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenSSL Project · OpenSSLversion=3.0.0 <3.0.8

Published CVSS scores

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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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