CVE-2026-4247 is a high-severity memory leak vulnerability (CVSS 7.5) affecting FreeBSD's TCP stack. The flaw occurs in the tcp_respond() function, which fails to consume mbufs when a challenge ACK is not sent, leading to resource exhaustion. An attacker on-path or with an established TCP connection can easily trigger these leaks, causing a denial of service. While off-path exploitation is possible but harder, there is no evidence of active exploitation, nor are public exploit modules available. Community discussion is minimal, and its EPSS score is very low, indicating a low likelihood of exploitation in the wild.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
14.3CPE matchmatch criteria | cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:* | ||
14.3CPE matchmatch criteria | cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:* | ||
14.3CPE matchmatch criteria | cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:* | ||
14.3CPE matchmatch criteria | cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:* | ||
14.3CPE matchmatch criteria | cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.