Critical severity · published Feb 16, 2022
CVE-2021-3773
A flaw in netfilter could allow a network-connected attacker to infer openvpn connection endpoint information for further use in traditional network attacks
9.8
CVSS
5.3%
EPSS
No
On KEV
Description
A flaw in netfilter could allow a network-connected attacker to infer openvpn connection endpoint information for further use in traditional network attacks.
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)5.3% · higher than 93% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
before 5.14; 5.15 before 5.15.15 · source: NVD
CC
Communications Cloud Native Core Binding Support Function · Oracle
22.1.3 · source: NVD
CC
Communications Cloud Native Core Network Exposure Function · Oracle
22.1.1 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
22.2.0 · source: NVD
EL
Enterprise Linux · Redhat
6.0; 7.0; 8.0 · source: NVD
FE
Fedora · Fedoraproject
34 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3773
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3773
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2004949
citizenlab.ca
https://citizenlab.ca/2024/07/vulnerabilities-in-vpns-paper-presented-at-the-privacy-enhancing-technologies-symposium-2024/
Patch
https://www.oracle.com/security-alerts/cpujul2022.html
security.netapp.com
https://security.netapp.com/advisory/ntap-20250328-0004/
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