7.5

CVE-2021-20027: sonicwall sonicos Classic Buffer Overflow

CVSS: 7.5v3.1HighModified
Published 14-06-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-20027 is a high (CVSS 7.5) Classic Buffer Overflow vulnerability in sonicwall sonicos. EPSS estimates a 1.29% chance of exploitation in the next 30 days, higher than 69.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
1.29%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 14-06-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A buffer overflow vulnerability in SonicOS allows a remote attacker to cause a Denial of Service (DoS) by sending a specially crafted request. This vulnerability affects SonicOS Gen5, Gen6, Gen7 platforms, and SonicOSv virtual firewalls.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

1.29%

Chance of exploitation in the next 30 days

Percentile

70%

Versus all other CVEs

30-day change

0.00 pp

From 1.29% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.29%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Sonicwall1 product
  • sonicosSonicOS 5.9.1.13 and earlier | SonicOSv 6.5.4.4 and earlier | SonicOS 6.0.5.3 and earlier | SonicOS 6.5.1.12 and earlier | SonicOS 6.5.4.7 and earlier | SonicOS 7.0.1-R1219 and earlier | SonicOS 7.0.1-R514 and earlier | SonicOS 7.0.1-R1262 and earlier | ≤ 7.0.1-r1262 | ≤ 7.0.1-r.1219 | ≤ 7.0.1-r514 | ≤ 5.9.1.13 | ≤ 6.5.1.12 | ≤ 6.5.4.7 | ≤ 6.0.5.3-94o

1 vendor · 1 product

References

1 links