MEDIUM · 5.3

CVE-2021-4138

Improved Host header checks to reject requests not sent to a well-known local hostname or IP, or the server-specified hostname.

Vulnerability Description

Improved Host header checks to reject requests not sent to a well-known local hostname or IP, or the server-specified hostname.

CVSS Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE

Affected Products

VendorProductVersions
MozillaGeckodriver< 0.30.0

References

FAQ

What is CVE-2021-4138?

CVE-2021-4138 is a vulnerability with a CVSS score of 5.3 (MEDIUM). Improved Host header checks to reject requests not sent to a well-known local hostname or IP, or the server-specified hostname.

How severe is CVE-2021-4138?

CVE-2021-4138 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-4138?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Geckodriver.