VulnerabilityDeferred

CVE-2026-53523

This can result in host header injection.

MEDIUM 6.8EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 1.0.0 to before version 2.2.0, the getRedirectURL function in oauth2.go:22-29 constructs the OAuth2 callback URL by concatenating the request's Host header with a fixed path, with zero validation of the Host header. This can result in host header injection. This issue has been patched in version 2.2.0.

CVSS 3.1: 6.8 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
EPSS: 0.24% probability · 15th percentile
CISA KEV: Not listed
Weakness: CWE-601
Source: security-advisories@github.com

References

https://github.com/nezhahq/nezha/security/advisories/GHSA-9rc6-8cjv-rcvx
https://github.com/nezhahq/nezha/security/advisories/GHSA-9rc6-8cjv-rcvx

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.