CVE-2026-45254Network attack vector

Network permission expansion via omitted limit keys

Published May 21, 2026 · Updated May 21, 2026

Privilege management failure in affected FreeBSD releases allows remote attackers to widen a sandboxed process's network permissions. The libcap_net limit-validation path treats family, hosts, or sockaddr keys omitted from a replacement limit as unrestricted instead of rejecting the widening request. Exposure requires libcap_net use on 14.3-RELEASE before p14, 14.4-RELEASE before p5, or 15.0-RELEASE before p9; no base-system software is affected.

CVSS severity6.5
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege management failure in affected FreeBSD releases allows remote attackers to widen a sandboxed process's network permissions. The libcap_net limit-validation path treats family, hosts, or sockaddr keys omitted from a replacement limit as unrestricted instead of rejecting the widening request. Exposure requires libcap_net use on 14.3-RELEASE before p14, 14.4-RELEASE before p5, or 15.0-RELEASE before p9; no base-system software is affected.

The record

CVE
CVE-2026-45254
Published
May 21, 2026
Updated
May 21, 2026
Vendor
The FreeBSD Project
Product
FreeBSD
Classifications
CWE-269
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 21, 2026CVE publishedPublication date reported by the CVE source.
  2. May 21, 2026Record 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=14.3-RELEASE <p14
  2. Affected versionversion=14.4-RELEASE <p5
  3. Affected versionversion=15.0-RELEASE <p9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The FreeBSD Project · FreeBSDversion=14.3-RELEASE <p14; version=14.4-RELEASE <p5; version=15.0-RELEASE <p9

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-269Improper Privilege Management

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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