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Vulnerabilities

Security fix · CVE-2026-58497

Uni-CLI: Legacy HTTP MCP transport accepted browser-originated localhost requests

Published Jun 19, 2026 · catalog updated Oct 24, 2026 · Uni-CLI: Legacy HTTP MCP

Check if you run it

No confirmed exploitation is on record for CVE-2026-58497. EPSS is 0.27%. Act only if a listed version of Uni-CLI: Legacy HTTP MCP is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (Uni-CLI: Legacy HTTP MCP).
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High—
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.27%
Remediation
Advisory link
Affected products
npm @zenalexa/unicli

## Impact Uni-CLI versions before 0.225.2 exposed the legacy JSON-RPC-over-HTTP MCP transport on loopback without validating browser Origin headers before routing requests. A malicious web page could send a CORS simple POST request, such as text/plain, to the local /mcp endpoint and deliver a JSON-RPC body to the dispatcher. If the user had started the local MCP HTTP transport, that page could drive tools/call requests against the user's local Uni-CLI server. The Streamable HTTP transport already enforced this browser-to-localhost boundary. The legacy stateless HTTP path did not, so the two HTTP transports had drifted. This issue is about the browser-to-localhost boundary; it does not change Uni-CLI's local-code-execution trust model. ## Patches Version 0.225.2 fixes the issue by moving the Origin policy into a shared guard and applying it before routing in both HTTP transports. Non-loopback browser Origins are rejected with HTTP 403 before health, OAuth, or /mcp dispatch runs. Non-browser clients that omit Origin remain supported. ## Workarounds Upgrade to 0.225.2 or later. If upgrading is not immediately possible, do not expose the legacy HTTP MCP transport to browser-originated traffic; use the default stdio transport or the Streamable HTTP transport instead. ## Credits Reported privately by Ryan Vonbrubeck ([@dodge1218](https://github.com/dodge1218)).

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • npm @zenalexa/unicli0 → 0.225.2

How to fix CVE-2026-58497

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-58497. EPSS is 0.27%. Act only if a listed version of Uni-CLI: Legacy HTTP MCP is installed.

Which versions are affected?

Compare what you have installed with 0 → 0.225.2. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-346; CWE-352: Cross-Site Request Forgery (CSRF). EPSS 0.27%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 19, 2026 · GitHub Advisory Database

    Detected

    ## Impact Uni-CLI versions before 0.225.2 exposed the legacy JSON-RPC-over-HTTP MCP transport on loopback without validating browser Origin headers before routing requests. A malicious web page could send a CORS simple POST request, such as text/plain, to the local /mcp endpoint and deliver a JSON-RPC body to the dispatcher. If the user had started the local MCP HTTP transport, that page could dri

  2. Oct 24, 2026 · GitHub Advisory Database

    Fix available

    @zenalexa/unicli fixed in 0.225.2

  3. Oct 24, 2026 · GitHub Advisory Database

    Fix available

    @zenalexa/unicli fixed in 0.225.2

  4. Oct 24, 2026 · GitHub Advisory Database

    Updated

    ## Impact Uni-CLI versions before 0.225.2 exposed the legacy JSON-RPC-over-HTTP MCP transport on loopback without validating browser Origin headers before routing requests. A malicious web page could send a CORS simple POST request, such as text/plain, to the local /mcp endpoint and deliver a JSON-RPC body to the dispatcher. If the user had started the local MCP HTTP transport, that page could dri

Sources

References

Freshness

Last verified in this catalog Oct 24, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.