Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:A) | Active user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Clear
About Google Cloud Build
CVE-2026-3136 affects Google Cloud Build, a product from Google. Before acting, confirm where Google Cloud Build runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: An improper authorization vulnerability in GitHub Trigger Comment Control in Google Cloud Build prior to 2026-1-26 allows a remote attacker to execute arbitrary code in the build environment. This vulnerability was patched on 26 January 2026, and no customer action is needed.
The weakness class is Incorrect Authorization. The permission check exists but gets the answer wrong.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and relies on a user taking an action. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Google Cloud Build |
| Affected versions | Cloud Build before 2026-1-26 |
| Published | Mar 3, 2026 |
| Last modified | Jun 17, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | f45cbf4e-4146-4068-b7e1-655ffc2c548c |
How to detect it
- Inventory every instance of Google Cloud Build and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Google Cloud Build named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Google Cloud Build to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-863: Incorrect Authorization More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
Incorrect authorization in Mojo in Google Chrome on on Windows prior to 155.0.8059.79 allowed a local attacker to potentially execute arbitrary code outside the sandbox via a local program. (Chromium security severity: High)
Information leak in Permissions in Google Chrome prior to 155.0.8059.39 allowed a remote attacker to bypass site isolation via a crafted HTML page. (Chromium security severity: Low)
Confused deputy in WebAPKs in Google Chrome on on Android prior to 155.0.8059.39 allowed a remote attacker leveraging social engineering to bypass web origin policy via a crafted HTML page. (Chromium security severity: Low)
Incorrect authorization in Actor in Google Chrome on on Android prior to 155.0.8059.39 allowed a remote attacker who had compromised the renderer process to potentially bypass site isolation via a crafted HTML page. (Chromium security severity: Low)
Missing authorization in FileSystem in Google Chrome prior to 155.0.8059.39 allowed a remote attacker who had compromised the renderer process to bypass web origin policy via a crafted HTML page. (Chromium security severity: Medium)
Missing authorization in Navigation in Google Chrome on on iOS prior to 155.0.8059.39 allowed a remote attacker to bypass web origin policy into a privileged page via a crafted HTML page. (Chromium security severity: Medium)
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