Vulnerability in Oisf Suricata
CVE-2019-18792
An issue was discovered in Suricata 5.0.0. It is possible to bypass/evade any tcp based signature by overlapping a TCP segment with a fake FIN packet. The fake FIN packet is injected just before the PUSH ACK packet we want to bypass. The PUSH ACK packet (containing the data) will be ignored by Suricata because it overlaps the FIN packet (the sequence and ack number are identical in the two packets). The client will ignore the fake FIN packet because the ACK flag is not set. Both linux and windows clients are ignoring the injected packet.
EPSS: 0.025 (83.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Oisf Suricata — versions 5.0.0
- Debian Debian_linux — versions 8.0
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (x_refsource_CONFIRM, Patch, Third Party Advisory)
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (x_refsource_CONFIRM, Patch, Third Party Advisory)
- cve@mitre.org (mailing-list, x_refsource_MLIST, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-18792?
- CVE-2019-18792 is a critical-severity vulnerability in Oisf Suricata, classified under CWE-436. CVSS score: 9.1/10. Published 2020-01-06.
- How severe is CVE-2019-18792?
- Critical severity. CVSS v3 base score is 9.1 out of 10.