CVE-2026-49352 is a critical-severity use of hard-coded credentials vulnerability in 9router (npm), affecting versions >= 0.2.21, <= 0.4.41. It is fixed in 0.4.45.
Summary 9router uses a publicly known hardcoded string "9router-default-secret-change-me" as the fallback of JWT secret for all Dashboard session JWTs when the JWTSECRET environment variable is not set. Because this secret is committed in the public repository and unchanged across all releases, any unauthenticated remote attacker can forge a valid authtoken cookie and gain full access to dashboard and api (If JWTSECRET is not set on server) . This vulnerable affected so many public 9router server Details | Versions | File | Note | |---|---|---| | >= 0.2.21, <= 0.4.30 | src/app/api/auth/login/route.js + src/middleware.js | Introduced in commit 23cfb19 | | >= 0.4.31, <= 0.4.41 | src/lib/auth/dashboardSession.js | Relocated by OIDC refactor c3d91b0, secret unchanged | Vulnerable Code v0.2.21 – v0.4.30, src/app/api/auth/login/route.js and src/middleware.js: v0.4.31 – v0.4.41 (current), src/lib/auth/dashboardSession.js (centralized via OIDC refactor, commit c3d91b0): The fallback string was introduced in commit 23cfb19 (2026-01-09) and has never been removed. The OIDC refactor in c3d91b0 only relocated it to a shared module . This vulnerability has existed since 9router first introduced authentication. PoC Step 1. Craft a JWT signed with the known default secret: Step 2. Set the forged token as the authtoken cookie. And access the http://<target>/dashboard - completely authentication bypass Attack Scenario: Attacker can use this JWT to spray to all server that they found in the internet and gain dashboard access if a server doesn't set JWTSECRET Then they can steal valuable API Key , Auth Token via http:// target /api/settings/database Impact A successful attack grants attacker full API Key, Auth Token that 9router hold They can read 9router apikey, change 9router password ,shutdown 9router, Modify everything Pivot via the MCP stdio→SSE bridge exposed at /api/mcp/ (exploit CVE-2026-46339) Recommended Fix Require JWTSECRET at startup and fail fast rather than falling back silently: Alternatively, auto-generate a random secret on first boot and persist it to the data directory, but never fall back to a publicly known constant.
Credentials are embedded in source code or a binary, making them accessible to anyone who can read the artifact. Typical impact: unauthorized access using the static credential.
CVE-2026-49352 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (0.4.45). Upgrading removes the vulnerable code path.
npm
9router (>= 0.2.21, <= 0.4.41)9router → 0.4.45 (npm)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
Kodem's runtime-powered SCA identifies whether CVE-2026-49352 is reachable in your applications. Explore open-source security for your team.
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Already deployed Kodem? See CVE-2026-49352 in your environment →Upgrade 9router to 0.4.45 or later to resolve this vulnerability.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-49352 is a critical-severity use of hard-coded credentials vulnerability in 9router (npm), affecting versions >= 0.2.21, <= 0.4.41. It is fixed in 0.4.45. Credentials are embedded in source code or a binary, making them accessible to anyone who can read the artifact.
CVE-2026-49352 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
9router (npm) versions >= 0.2.21, <= 0.4.41 is affected.
Yes. CVE-2026-49352 is fixed in 0.4.45. Upgrade to this version or later.
Whether CVE-2026-49352 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade 9router to 0.4.45 or later.