Medium 4.3Published Sep 27, 2026

CVE-2026-101087Nezha 2.0.10 through 2.3.2 SSRF Denylist Bypass IPv6

Updated under an hour ago (2026-10-19 08:50 UTC)

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Every CVE for nezhahq nezha

Exploited in the last 30 days

Nezha versions 2.0.10 through 2.3.2 use a restricted HTTP client to validate user-configurable notification and DDNS webhook URLs, but the denylist did not cover IPv6 transition ranges — specifically the 6to4 prefix 2002::/16 and the local-use IPv4/IPv6 translation prefix 64:ff9b:1::/48. Because such addresses satisfy Go's netip.Addr.IsGlobalUnicast check, the URL validator accepted them. An authenticated user able to configure a webhook may be able to cause the dashboard to issue requests to an otherwise restricted IPv6 endpoint, but only where the dashboard's network provides unusual or non-standards-compliant routing for these transition ranges; no direct path to an IPv4 metadata, loopback, or private-network HTTP request has been demonstrated. The issue is fixed in version 2.3.3 (commit d1fcde8e), which blocks both prefixes.

CVSS: 4.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weakness (CWE): CWE-918
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Sep 30, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

nezhahq nezha nezhahq:nezha (from the name)	from 2.0.10 before 2.3.3; 2.3.3 not affected	CNA record

References

https://github.com/nezhahq/nezha/security/advisories/GHSA-jr2j-7hvh-h4q9vendor-advisory
https://github.com/nezhahq/nezha/commit/d1fcde8epatch
https://www.vulncheck.com/advisories/nezha-2.0.10-through-2.3.2-ssrf-denylist-bypass-ipv6third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.