Out-of-bounds write in Tcpreplay - #VU139350
Published: July 24, 2026
Vulnerability identifier: #VU139350
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code or cause a denial of service.
The vulnerability exists due to out-of-bounds write in tcprewrite fragroute tcp_seg and ip_frag modules when parsing a negative size value from an attacker-influenced fragroute rules file. A remote attacker can supply a specially crafted rules file to execute arbitrary code or cause a denial of service.
Exploitation requires tcprewrite to be built with libdnet fragroute support and invoked with the --fragroute option. No crafted packet content is required.
Affected software
Tcpreplay
Remediation
Install security update from vendor's website.
Tcpreplay - addressed in versions 4.5.5, 4.6.0 beta2