CVE-2021-36809

MEDIUMNVD 6.16.0▼

6.1

A local attacker can overwrite arbitrary files on the system with VPN client logs using administrator privileges, potentially resulting in a denial of service and data loss, in all versions of Sophos SSL VPN client.

CVSS v3: 6.1
EG Score: 6.0(medium)
EPSS: 15.0%
KEV: Not listed

Published

March 8, 2022

Last Modified

November 21, 2024

References (2)

security-alert@sophoshttps://www.sophos.com/en-us/security-advisories/sophos-sa-20220303-sslvpn-local-dos
af854a3a-2127-422b-91ae-364da2661108https://www.sophos.com/en-us/security-advisories/sophos-sa-20220303-sslvpn-local-dos

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-269Improper Privilege Management

Data Freshness Timeline

(refreshed 16× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

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Frequently asked(5)

What is CVE-2021-36809?

CVE-2021-36809 is a medium vulnerability published on March 8, 2022. A local attacker can overwrite arbitrary files on the system with VPN client logs using administrator privileges, potentially resulting in a denial of service and data loss, in all versions of Sophos SSL VPN client.

When was CVE-2021-36809 disclosed?

CVE-2021-36809 was first published in the National Vulnerability Database on March 8, 2022, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-36809 actively exploited?

CVE-2021-36809 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 15.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-36809?

CVE-2021-36809 has a CVSS v3 base score of 6.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.0.

How do I remediate CVE-2021-36809?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-36809, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-36809

📅 Published

🔄 Last Modified

🔗 References (2)

Weakness Classification(1)

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-36809?

🔗 Related CVEs(same CWE)

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Published

Last Modified

References (2)

Frequently asked(5)

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