High severity · published Jan 10, 2022
CVE-2021-20046
A Stack-based buffer overflow in the SonicOS HTTP Content-Length response header allows a remote authenticated attacker to cause Denial of Service (DoS) and potentially results in…
8.8
CVSS
1.9%
EPSS
No
On KEV
Description
A Stack-based buffer overflow in the SonicOS HTTP Content-Length response header allows a remote authenticated attacker to cause Denial of Service (DoS) and potentially results in code execution in the firewall. This vulnerability affected SonicOS Gen 5, Gen 6 and Gen 7 firmware versions.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SO
Sonicos · Sonicwall
through 7.0.1-r146; through 7.0.1-5023-1349; through 7.0.1-5018-r1715; through 6.5.4.8-89n; through 6.5.1.13-1n; through 6.0.5.3-94o; +1 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20046
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20046
Vendor Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0027
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