CVE-2026-126837

Attacker able to redirect a client's database traffic to a host they control via special characters in an SRV target, bypassing the SRV parent-domain guard

  • Critical 9.1

Description

A validation flaw in the DNS SRV host discovery of the MongoDB Node.js driver may cause the driver to connect to a host outside the expected domain. For a mongodb+srv:// connection string, the driver checks each host name in the DNS SRV response against the domain of the connection string. The driver then builds the connection address from the original name, in which certain characters end the host name early. An unauthenticated party who can forge or change the DNS SRV response may redirect the connection to a host of their choice. TLS does not prevent this, because the driver verifies the server certificate against the redirected host name. This may result in unintended disclosure of application data and authentication credentials, and in altered query results. Applications that use mongodb:// connection strings are not affected.

Key facts

Published
12 Nov 2026
Last changed
13 Nov 2026
Assigned by
mongodb
EPSS
0.205% likely to be exploited in the next 30 days, higher than 10.583% of CVEs (scores for 15 Nov 2026)
SSVC (CISA)
Exploitation: none; Automatable: no; Technical impact: total

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 9.1CVSS 4.0, Criticalfrom the CNA (mongodb)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
  • 7.4CVSS 3.1, Highfrom the CNA (mongodb)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
MongoDBNode.js Driver
  • Default status: unaffected
  • 3.3.3 up to but excluding 7.8.0 (affected)

Timeline

  1. 12 Nov 2026 Published

Weakness

References