CVE-2026-119600: simsong tcpflow · Improper Handling of Length Parameter Inconsistency
Affects simsong tcpflowSource CVE Database V5
Not known to be exploited · CVSS 6.3 Medium.
Data as of 30 Oct 2026, 13:48 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 6.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 4.8 |
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| simsongtcpflow | Affected
| Fixed in– |
GitHubtcpflowpkg:github/tcpflowOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
tcpflow through 1.6.1 contains an out-of-bounds read vulnerability that allows unauthenticated attackers to read process memory by sending packets with forged IP payload lengths. Attackers can inject crafted IPv4 or IPv6 TCP packets into captured traffic or pcap files to leak adjacent memory into reconstructed flow files or crash tcpflow.
References
- github.com/simsong/tcpflow/issues/279 (opens in a new tab)
- github.com/simsong/tcpflow/blob/tcpflow-1.6.1/src/tcpdemux.cpp (opens in a new tab)
- github.com/simsong/tcpflow/blob/tcpflow-1.6.1/src/tcpdemux.cpp (opens in a new tab)
- hackmd.io/@haindpwn/tcpflow-ip-payload-length-oob-read (opens in a new tab)
- github.com/simsong/tcpflow (opens in a new tab)
- vulncheck.com/advisories/tcpflow-through-1.6.1-out-of-bounds-read-via-tcp-demultiplexer-payload-length (opens in a new tab)