VULNpocalypse

CVE-2026-62264: PDF Reader MCP: HTTP transport accepts unauthenticated requests despite a configured MCP_API_KEY

Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.

Generated by VEDAS. Scores as of 2026-11-11 15:49 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.

What it is

PDF Reader MCP is a Model Context Protocol server for reading PDF documents. In versions 2.2.0 and later prior to 3.0.1, when `MCP_TRANSPORT=http` enables the opt-in HTTP server, `@sylphx/pdf-reader-mcp` reads `MCP_API_KEY` and logs that `X-API-Key` authentication is enabled but never validates the `X-API-Key` header on incoming requests. The `/mcp` endpoint consequently accepts unauthenticated clients. With the default bind address of `0.0.0.0`, any client able to reach the port can invoke every PDF tool and read any PDF the server process can open on the host, despite the misleading authentication-enabled startup log. URL-based sources additionally permit limited server-side request forgery; private and loopback destinations are blocked by default unless `--allow-private-ips` is set. The default `stdio` transport is unaffected. This issue is fixed in version 3.0.1.

Description quoted from the CVE record (assigned by GitHub_M, published 2026-10-30).

Weakness: CWE-200: Exposure of Sensitive Information to an Unauthorized Actor; CWE-287: Improper Authentication; CWE-306: Missing Authentication for Critical Function

How it can be exploited

Exploitable over the network with low attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity none, availability none. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA assessment (SSVC): CISA has no evidence of exploitation. Automatable: yes. Technical impact: partial.

Public exploit evidence (Exploit Observer)

Exploit Observer found 5 code repositories naming this CVE.

Code repositories that name a CVE are often scanners, copies or fakes, and some are malware. Read the code before running anything.

See all 8 references on Exploit Observer

Live scores

EPSS
0.005
low predicted chance of attack
VEDAS
0.986
strong exploit evidence
On CISA KEV
Not listed
Detection rule
Nuclei · Suricata

Who is affected

ProductAffectedNot affected
SylphxAI pdf-reader-mcpversion >= 2.2.0, < 3.0.1Not stated

Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.

How to fix it

No fixed version or vendor advisory is listed in the CVE record yet. Watch the vendor’s security page.

How to detect it

Nuclei template (active check)

PDF Reader MCP - Unauthenticated MCP Server Access

PDF Reader MCP (`@sylphx/pdf-reader-mcp`) versions 2.2.0 and later prior to 3.0.1, when `MCP_TRANSPORT=http` enables the opt-in HTTP server, read `MCP_API_KEY` and log that `X-API-Key` authentication is enabled but never validate the `X-API-Key` header. The `/mcp` endpoint therefore accepts unauthenticated clients, and with the default bind address of 0.0.0.0 any reachable client can invoke every PDF tool and read any PDF the server process can open. This template performs an unauthenticated MCP initialize handshake. Fixed in 3.0.1.

Name and description quoted from the template, written by VEDAS.

The template sends 1 request (POST /mcp); it decides using dsl matchers. Severity in the template: high. Marked as not yet verified against a live vulnerable target.

Run it against a host you own or are authorised to test:

bash
nuclei -u https://your-host -t CVE-2026-62264.yaml
Show the template (42 lines)
yaml
id: CVE-2026-62264

info:
  name: "PDF Reader MCP - Unauthenticated MCP Server Access"
  author: vedas-arpsyndicate
  severity: high
  description: |
    PDF Reader MCP (`@sylphx/pdf-reader-mcp`) versions 2.2.0 and later prior to 3.0.1, when
    `MCP_TRANSPORT=http` enables the opt-in HTTP server, read `MCP_API_KEY` and log that
    `X-API-Key` authentication is enabled but never validate the `X-API-Key` header. The `/mcp`
    endpoint therefore accepts unauthenticated clients, and with the default bind address of
    0.0.0.0 any reachable client can invoke every PDF tool and read any PDF the server process can
    open. This template performs an unauthenticated MCP initialize handshake. Fixed in 3.0.1.
  reference:
    - https://www.exploit.observer/?keyword=CVE-2026-62264&match=exact
    - https://subdomain.center/?engine=ammonites&keyword=pdf-reader-mcp&match=exact
  classification:
    cve-id: CVE-2026-62264
    cwe-id: CWE-306
  metadata:
    verified: false
    max-request: 1
  tags: cve,cve2026,pdf-reader-mcp,auth-bypass
http:
  - raw:
      - |
        POST /mcp HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json
        Accept: application/json, text/event-stream

        {"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"vedas","version":"1.0"}}}

    matchers-condition: and
    matchers:
      - type: dsl
        dsl:
          - 'status_code == 200'
          - 'contains(body, "\"jsonrpc\"")'
          - 'contains(body, "\"result\"")'
          - 'contains(body, "protocolVersion")'
        condition: and

CVE-2026-62264.yaml on GitHub

Suricata rules (network detection)

1 rule that alert on traffic matching this exploit: VEDAS CVE-2026-62264 PDF Reader MCP - Unauthenticated MCP Server Access. Add them to your Suricata rule set and reload.

Show the rules
suricata
alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2026-62264 PDF Reader MCP - Unauthenticated MCP Server Access"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/mcp"; nocase; fast_pattern; http.request_body; content:"initialize"; nocase; content:"jsonrpc"; nocase; classtype:web-application-attack; reference:cve,CVE-2026-62264; reference:url,https://www.exploit.observer/?keyword=CVE-2026-62264&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=pdf-reader-mcp&match=exact; sid:1103003; rev:1;)

CVE-2026-62264.rules on GitHub

References

Other references

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, cve-scores (EPSS and VEDAS), Exploit Observer, vedas-signatures. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.

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