How severe is CVE-2022-36436?

CVE-2022-36436 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2022-36436 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-36436?

CVE-2022-36436 affects Osuosl Twisted Vnc Authentication Proxy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-36436?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2022-36436 published?

CVE-2022-36436 was published on 2022-09-14 and last updated on 2026-06-17.

CVE-2022-36436

CVE-2022-36436 is a critical-severity vulnerability in Osuosl Twisted Vnc Authentication Proxy with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Osuosl Twisted Vnc Authentication Proxy
Published: 2022-09-14
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2022-36436?: 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.
How severe is CVE-2022-36436?: CVE-2022-36436 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2022-36436 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-36436?: CVE-2022-36436 affects Osuosl Twisted Vnc Authentication Proxy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-36436?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2022-36436 published?: CVE-2022-36436 was published on 2022-09-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:osuosl:twisted_vnc_authentication_proxy:*:*:*:*:*:*:*:*

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