5.3
MEDIUM CVSS 4.0
CVE-2026-101087
Nezha 2.0.10 through 2.3.2 SSRF Denylist Bypass IPv6
Description

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.

INFO

Published Date :

Sept. 27, 2026, 9:17 p.m.

Last Modified :

Sept. 27, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-101087 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update Nezha to version 2.3.3 or later to block restricted IPv6 prefixes.
  • Update Nezha to version 2.3.3 or later.
  • Block restricted IPv6 transition prefixes.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-101087.

URL Resource
https://github.com/nezhahq/nezha/commit/d1fcde8e
https://github.com/nezhahq/nezha/security/advisories/GHSA-jr2j-7hvh-h4q9
https://www.vulncheck.com/advisories/nezha-2.0.10-through-2.3.2-ssrf-denylist-bypass-ipv6
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-101087 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-101087 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-101087 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-101087 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 27, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
    Added CWE CWE-918
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/101xxx/CVE-2026-101087.json">CVE-2026-101087</a>
    Added Reference https://github.com/nezhahq/nezha/commit/d1fcde8e
    Added Reference https://github.com/nezhahq/nezha/security/advisories/GHSA-jr2j-7hvh-h4q9
    Added Reference https://www.vulncheck.com/advisories/nezha-2.0.10-through-2.3.2-ssrf-denylist-bypass-ipv6
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.