CVE-2026-93315Hinoki check available

Build disruption via mutable CA cleanup target

Published Oct 5, 2026 · Updated Oct 5, 2026

Improper cleanup in Moby Project BuildKit 0.31.0 through 0.33.0 allows local users to disrupt builds or affect files outside a build rootfs. With proxy networking and CA injection enabled, a build step can change its CA bundle before BuildKit cleans it up, causing cleanup to use attacker-controlled filesystem state. The issue requires proxy networking for exec steps; a special file can block cleanup, and cleanup failure can leave a build reported as successful.

CVSS severity5.8
Medium
EPSS probability0.10%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper cleanup in Moby Project BuildKit 0.31.0 through 0.33.0 allows local users to disrupt builds or affect files outside a build rootfs. With proxy networking and CA injection enabled, a build step can change its CA bundle before BuildKit cleans it up, causing cleanup to use attacker-controlled filesystem state. The issue requires proxy networking for exec steps; a special file can block cleanup, and cleanup failure can leave a build reported as successful.

The record

CVE
CVE-2026-93315
Published
Oct 5, 2026
Updated
Oct 5, 2026
Vendor
Moby Project
Product
BuildKit
Classifications
CWE-367, T1499.004
Attack vector
local
Privileges
authenticated

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?

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  1. Affected versionversion=0.31.0 <0.33.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Moby Project · BuildKitversion=0.31.0 <0.33.1

Published CVSS scores

5.8Moby ProjectCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
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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