Vulnerability Details : CVE-2019-18625
An issue was discovered in Suricata 5.0.0. It was possible to bypass/evade any tcp based signature by faking a closed TCP session using an evil server. After the TCP SYN packet, it is possible to inject a RST ACK and a FIN ACK packet with a bad TCP Timestamp option. The client will ignore the RST ACK and the FIN ACK packets because of the bad TCP Timestamp option. Both linux and windows client are ignoring the injected packets.
Exploit prediction scoring system (EPSS) score for CVE-2019-18625
Probability of exploitation activity in the next 30 days: 0.21%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 58 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2019-18625
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source |
---|---|---|---|---|---|
5.0
|
MEDIUM | AV:N/AC:L/Au:N/C:N/I:P/A:N |
10.0
|
2.9
|
NIST |
7.5
|
HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
3.9
|
3.6
|
NIST |
References for CVE-2019-18625
-
https://github.com/OISF/suricata/commit/9f0294fadca3dcc18c919424242a41e01f3e8318
stream: fix SYN_SENT RST/FIN injection · OISF/suricata@9f0294f · GitHubPatch;Third Party Advisory
-
https://lists.debian.org/debian-lts-announce/2020/01/msg00032.html
[SECURITY] [DLA 2087-1] suricata security updateMailing List;Third Party Advisory
-
https://redmine.openinfosecfoundation.org/issues/3395
Bug #3395: TCP evasion technique by faking a closed TCP session (4.1.x) - Suricata - Open Information Security FoundationThird Party Advisory
-
https://github.com/OISF/suricata/commit/ea0659de7640cf6a51de5bbd1dbbb0414e4623a0
stream: fix SYN_SENT RST/FIN injection · OISF/suricata@ea0659d · GitHubPatch;Third Party Advisory
-
https://redmine.openinfosecfoundation.org/issues/3286
Bug #3286: TCP evasion technique by faking a closed TCP session - Suricata - Open Information Security FoundationThird Party Advisory
Products affected by CVE-2019-18625
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:suricata-ids:suricata:5.0.0:-:*:*:*:*:*:*