CVE-2023-29323

Service crash via unsupported scoped IPv6 parsing

Published Apr 4, 2023 · Updated Nov 4, 2025

Address parsing in OpenBSD smtpd 7.1 and 7.2 and OpenSMTPD Portable before 7.0.0-portable allows local users to crash smtpd. ascii_load_sockaddr passes bracketed IPv6 text to inet_pton, which rejects scope identifiers; the failed conversion propagates to an abort instead of producing a usable socket address. Reachability requires an SMTP connection from a scoped link-local IPv6 address, and the bounded consequence is interruption of the smtpd service.

CVSS severity7.8
High
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Address parsing in OpenBSD smtpd 7.1 and 7.2 and OpenSMTPD Portable before 7.0.0-portable allows local users to crash smtpd. ascii_load_sockaddr passes bracketed IPv6 text to inet_pton, which rejects scope identifiers; the failed conversion propagates to an abort instead of producing a usable socket address. Reachability requires an SMTP connection from a scoped link-local IPv6 address, and the bounded consequence is interruption of the smtpd service.

The record

CVE
CVE-2023-29323
Published
Apr 4, 2023
Updated
Nov 4, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Apr 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.8CanonicalCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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