CVE-2026-3259Network attack vector

Protected-data disclosure via refresh error messages

Published Apr 23, 2026 · Updated Apr 23, 2026

Sensitive-data exposure in Google BigQuery before 29 January 2026 allows remote authenticated users to read protected query data. During a crafted materialized-view refresh, the runtime error path includes masked or filtered data protected by fine-grained access-control policies in the returned error message. Reachability requires authenticated permission to create or refresh the crafted view; disclosure is limited to data surfaced by the error.

CVSS severity7.1
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive-data exposure in Google BigQuery before 29 January 2026 allows remote authenticated users to read protected query data. During a crafted materialized-view refresh, the runtime error path includes masked or filtered data protected by fine-grained access-control policies in the returned error message. Reachability requires authenticated permission to create or refresh the crafted view; disclosure is limited to data surfaced by the error.

The record

CVE
CVE-2026-3259
Published
Apr 23, 2026
Updated
Apr 23, 2026
Vendor
Go standard library
Product
BigQuery
Classifications
CWE-209, CAPEC-54, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 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 <01/29/2026

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Go standard library · BigQueryversion=0 <01/29/2026

Published CVSS scores

7.1Google CloudCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-209Generation of Error Message Containing Sensitive Information
CAPEC-54Query System for Information
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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