TI-2025-18628 Aliases CVE-2025-24934 GHSA-h546-6x4h-w6q7

SO_REUSEPORT_LB breaks connect(2) for UDP sockets

LOW 24CWE-488Published 2025-10-22 · Updated 2026-04-23

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: Low · Low · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

Software which sets SO_REUSEPORT_LB on a socket and then connects it to a host will not directly observe any problems. However, due to its membership in a load-balancing group, that socket will receive packets originating from any host. This breaks the contract of the connect(2) and implied connect via sendto(2), and may leave the application vulnerable to spoofing attacks. The kernel failed to check the connection state of sockets when adding them to load-balancing groups. Furthermore, when looking up the destination socket for an incoming packet, the kernel will match a socket belonging to a load-balancing group even if it is connected, in violation of the contract that connected sockets are only supposed to receive packets originating from the connected host.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00215 11th percentileScored 2026-11-07

Fix Fixed FreeBSD (FreeBSD): p1, p5, p6

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
FreeBSD	FreeBSD	15.0-BETA2 to before p1; 14.3-RELEASE to before p5; 13.5-RELEASE to before p6	p1, p5, p6	Patch available	CNA

FreeBSD VendorFreeBSD Affected 15.0-BETA2 to before p1; 14.3-RELEASE to before p5; 13.5-RELEASE to before p6 Fixed in p1, p5, p6 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:o:freebsd:freebsd::::::::	—	—	FreeBSD

cpe:2.3:o:freebsd:freebsd:*:*:*:*:*:*:*:* Versions — — ·FreeBSD

Remediation

Fix · CNA FreeBSD (FreeBSD) Fixed in p1, p5, p6

Timeline

2026-10-02 Threatist record created from CVE-2025-24934
2026-10-03 Alias added: GHSA-h546-6x4h-w6q7

References

Advisory 1

https://security.freebsd.org/advisories/FreeBSD-SA-25:09.netinet.asc

Other 1

https://www.usenix.org/system/files/conference/usenixsecurity26/sec26_prepub_ben-simhon.pdf

TI-2011-04182 Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT… CVSS 2.0HIGH 10.0
TI-2007-03684 Integer overflow in print-bgp.c in the BGP dissector in tcpdump 3.9.6 and earlier allows… CVSS 3.1CRITICAL 9.8
TI-2002-00376 Integer overflow in xdr_array function in RPC servers for operating systems that use… CVSS 3.1CRITICAL 9.8
TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
TI-2003-00437 Off-by-one error in the fb_realpath() function, as derived from the realpath function in… CVSS 3.1CRITICAL 9.8
TI-2003-00642 The prescan function in Sendmail 8.12.9 allows remote attackers to execute arbitrary code… CVSS 2.0HIGH 10.0

See all 611 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences