CVE-2026-55641
Host header auth bypass in 9Router allows unauthenticated proxying and SSRF.
Is CVE-2026-55641 being exploited?
Not confirmed. CVE-2026-55641 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.32% probability of exploitation in the next 30 days.
How severe is CVE-2026-55641?
CVE-2026-55641 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-55641?
Yes. A fix has been recorded for CVE-2026-55641. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-55641 affect?
CVE-2026-55641 affects 9Router < 0.5.2, /v1 proxy endpoint, /v1/search (searxng provider_options.baseUrl). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-55641?
Upgrade 9Router to v0.5.2 and validate Host header handling; restrict metadata access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated attacker can bypass API-key auth via Host header, trigger upstream LLM calls with stored provider creds and perform SSRF to internal/cloud metadata.
Patch when possible
- affected< 0.5.2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.