CVE-2019-18625
mediumpriority · track · 31EPSS 0.017 · 77 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 5–9.1
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (7)
Products and version ranges known to be affected.
also known as (4)
Other names and identifiers for this entity.
sources
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references (18)
External citations — patches, advisories, analysis.
- https://github.com/OISF/suricata/commit/9f0294fadca3dcc18c919424242a41e01f3e8318cnnvd
- https://github.com/OISF/suricata/commit/ea0659de7640cf6a51de5bbd1dbbb0414e4623a0cnnvd
- https://lists.debian.org/debian-lts-announce/2020/01/msg00032.htmlcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-18625cnnvd
- https://redmine.openinfosecfoundation.org/issues/3286cnnvd
- https://redmine.openinfosecfoundation.org/issues/3395cnnvd
- https://vigilance.fr/vulnerability/Suricata-privilege-escalation-via-TCP-Timestamp-Signature-Bypass-31466cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.0366/cnnvd
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