CVSS 4.0
9.1 criticalCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NCVE-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) in mongodb node.js driver. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
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.
Severity
CVSS 3.1
7.4 highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 11th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: total, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-180 Incorrect Behavior Order: Validate Before Canonicalize
- Published
- Modified
- Assigned by
- mongodb (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- mongodb:node.js driver
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| MongoDB Node.js Driver | from 3.3.3 before 7.8.0 |
Attack patterns (CAPEC)
- CAPEC-3 Using Leading 'Ghost' Character Sequences to Bypass Input Filters Likelihood: Medium · Severity: Medium
- CAPEC-71 Using Unicode Encoding to Bypass Validation Logic Likelihood: Medium · Severity: High
- CAPEC-78 Using Escaped Slashes in Alternate Encoding Likelihood: High · Severity: High
- CAPEC-79 Using Slashes in Alternate Encoding Likelihood: High · Severity: High
- CAPEC-80 Using UTF-8 Encoding to Bypass Validation Logic Likelihood: High · Severity: High
- CAPEC-267 Leverage Alternate Encoding Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.