Critical severity · published Oct 10, 2023
CVE-2020-27631
In Oryx CycloneTCP 1.9.6, TCP ISNs are improperly random
9.8
CVSS
1.1%
EPSS
No
On KEV
Description
In Oryx CycloneTCP 1.9.6, TCP ISNs are improperly random.
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)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CY
Cyclonetcp · Oryx-embedded
1.9.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-27631
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-27631
Third Party Advisory
https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01
Third Party Advisory
https://www.forescout.com
Third Party Advisory
https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/
More from Cyclonetcp
7.5
CVE-2021-26788
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS)