CVE-2026-28406Network attack vector

Arbitrary file writes via context archive traversal

Published Feb 27, 2026 · Updated Feb 27, 2026

Path traversal in Chainguard kaniko 1.25.4 through 1.25.9 allows remote attackers to write files outside the extraction root. The ExtractFile path in pkg/util/fs_util.go joins a cleaned tar entry name to the destination without verifying that the result remains beneath that directory. A crafted build-context archive can overwrite files available to the executor, and registry authentication enables a credential-helper chain to execute code in that process.

CVSS severity8.2
High
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Chainguard kaniko 1.25.4 through 1.25.9 allows remote attackers to write files outside the extraction root. The ExtractFile path in pkg/util/fs_util.go joins a cleaned tar entry name to the destination without verifying that the result remains beneath that directory. A crafted build-context archive can overwrite files available to the executor, and registry authentication enables a credential-helper chain to execute code in that process.

The record

CVE
CVE-2026-28406
Published
Feb 27, 2026
Updated
Feb 27, 2026
Vendor
Chainguard
Product
kaniko
Classifications
CWE-22, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 27, 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=>= 1.25.4, < 1.25.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Chainguard · kanikoversion=>= 1.25.4, < 1.25.10

Published CVSS scores

8.2GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

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 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-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1203Exploitation for Client Execution

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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