CVE-2026-93321Hinoki check available

Daemon crash via invalid symlink owner input

Published Oct 5, 2026 · Updated Oct 5, 2026

Denial of service in Moby Project BuildKit 0.33.0 and earlier allows attackers to crash buildkitd through a crafted frontend LLB file operation. The LLB file-operation handler accepts invalid symlink owner input instead of rejecting the malformed definition, causing a daemon panic. Exploitation requires an untrusted external frontend; the crash terminates builds on that daemon, while ordinary Dockerfile builds are unaffected.

CVSS severity6.9
Medium
EPSS probability0.15%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Denial of service in Moby Project BuildKit 0.33.0 and earlier allows attackers to crash buildkitd through a crafted frontend LLB file operation. The LLB file-operation handler accepts invalid symlink owner input instead of rejecting the malformed definition, causing a daemon panic. Exploitation requires an untrusted external frontend; the crash terminates builds on that daemon, while ordinary Dockerfile builds are unaffected.

The record

CVE
CVE-2026-93321
Published
Oct 5, 2026
Updated
Oct 5, 2026
Vendor
Moby Project
Product
BuildKit
Classifications
CWE-129, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 5, 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=0 <=0.33.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Moby Project · BuildKitversion=0 <=0.33.0

Published CVSS scores

6.9Moby ProjectCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA: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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-129Improper Validation of Array Index
T1499.004Endpoint Denial of Service: Application 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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