CVE-2026-67638Network attack vector

Authenticated code execution via TDS RPC overflow

Published Sep 8, 2026 · Updated Sep 10, 2026

Heap-based buffer overflow in Microsoft SQL Server 2025 allows remote authenticated users to execute code through a TDS RPC request. The SQL Server Engine fails to enforce buffer bounds while processing an authenticated Tabular Data Stream remote procedure call, allowing attacker-controlled data to overwrite heap memory. A valid database login and network access to the instance are required; successful exploitation grants code execution in the SQL Server process.

CVSS severity8.8
High
EPSS probability0.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in Microsoft SQL Server 2025 allows remote authenticated users to execute code through a TDS RPC request. The SQL Server Engine fails to enforce buffer bounds while processing an authenticated Tabular Data Stream remote procedure call, allowing attacker-controlled data to overwrite heap memory. A valid database login and network access to the instance are required; successful exploitation grants code execution in the SQL Server process.

The record

CVE
CVE-2026-67638
Published
Sep 8, 2026
Updated
Sep 10, 2026
Vendor
Microsoft
Product
Microsoft SQL Server 2025
Classifications
CWE-122, T1210
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 10, 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=17.0.0.0 <17.0.4085.5
  2. Affected versionversion=17.0.1050.2 <17.0.1135.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft SQL Server 2025version=17.0.0.0 <17.0.4085.5; version=17.0.1050.2 <17.0.1135.8

Published CVSS scores

8.8MicrosoftCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1210Exploitation of Remote Services

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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