CVE-2019-18792 Security feature bypass in n/a

What is CVE-2019-18792?

CVE-2019-18792 is a critical vulnerability in Debian Debian Linux, published on 6 Jan 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-436

Which versions are affected by CVE-2019-18792?

It affects 2 products.

Products include Debian Debian Linux, Oisf Suricata.

How do I fix CVE-2019-18792?

Upgrade to a fixed version.

Is CVE-2019-18792 being exploited?

There is no known exploitation of CVE-2019-18792 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

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• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2019-18792, GHSA-p4hg-mvq8-47jj, UBUNTU-CVE-2019-18792.