CyberSecBulletin
CVE-2026-70003NVD status: Awaiting Analysis

Microsoft JDBC Driver for SQL Server 13.4: Improper Verification of Cryptographic Signature

Published Updated By the CyberSecBulletin desk

CVE-2026-70003 is a high-severity improper verification of cryptographic signature vulnerability in Microsoft JDBC Driver for SQL Server 13.4 from Microsoft, with a CVSS 3.1 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 13.6.0 as the first without the flaw, so updating Microsoft JDBC Driver for SQL Server 13.4 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.3% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Microsoft JDBC Driver for SQL Server 13.4 to 13.6.0 or a later version.
  2. Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MicrosoftMicrosoft JDBC Driver for SQL Server 13.41.0.0 up to, but not including, 13.6.013.6.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N. Scored by CNA (microsoft.com).

Official description

Improper verification of cryptographic signature in JDBC Driver for SQL Server allows an unauthorized attacker to bypass a security feature over a network.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Verification of Cryptographic Signature

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Verification of Cryptographic Signature vulnerabilities

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