CVE-2025-24934
SO_REUSEPORT_LB breaks connect(2) for UDP sockets
Description
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.
INFO
Published Date :
Oct. 22, 2025, 6:15 p.m.
Last Modified :
Oct. 22, 2025, 9:12 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update the system kernel to the latest version.
- Apply security patches for socket handling.
- Verify socket connection state after updates.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-24934.
| URL | Resource |
|---|---|
| https://security.freebsd.org/advisories/FreeBSD-SA-25:09.netinet.asc |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-24934 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-24934
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-24934 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-24934 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 22, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N -
New CVE Received by [email protected]
Oct. 22, 2025
Action Type Old Value New Value Added Description 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. Added CWE CWE-488 Added Reference https://security.freebsd.org/advisories/FreeBSD-SA-25:09.netinet.asc