What is CVE-2021-42711?

CVE-2021-42711 is a high-severity vulnerability in Barracuda Network Access Client, classified under Incorrect Default Permissions. CVSS score: 7.8/10. Published 2021-12-01.

How severe is CVE-2021-42711?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2021-42711 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Barracuda Network Access Client

CVE-2021-42711

Barracuda Network Access Client before 5.2.2 creates a Temporary File in a Directory with Insecure Permissions. This file is executed with SYSTEM privileges when an unprivileged user performs a repair operation.

Published 2021-12-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (17.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Barracuda Network Access Client

Weakness classification (CWE)

CWE-276 — Incorrect Default Permissions

Public proof-of-concept exploits

References

github.com/mandiant/Vulnerability-Disclosures/blob/master/MNDT-2021-0010/MNDT-2… (Third Party Advisory)

Frequently asked questions

What is CVE-2021-42711?: CVE-2021-42711 is a high-severity vulnerability in Barracuda Network Access Client, classified under Incorrect Default Permissions. CVSS score: 7.8/10. Published 2021-12-01.
How severe is CVE-2021-42711?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-42711 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.