Critical severity · published Jan 29, 2026
CVE-2020-36997
BacklinkSpeed 2.4 contains a buffer overflow vulnerability that allows attackers to corrupt the Structured Exception Handler (SEH) chain through malicious file import
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
BacklinkSpeed 2.4 contains a buffer overflow vulnerability that allows attackers to corrupt the Structured Exception Handler (SEH) chain through malicious file import. Attackers can craft a specially designed payload file to overwrite SEH addresses, potentially executing arbitrary code and gaining control of the application.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36997
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-36997
www.dummysoftware.com
http://www.dummysoftware.com
www.dummysoftware.com
http://www.dummysoftware.com/backlinkspeed.html
www.exploit-db.com
https://www.exploit-db.com/exploits/48726
www.vulncheck.com
https://www.vulncheck.com/advisories/backlinkspeed-buffer-overflow-poc-seh