Search/CVE-2025-21854
● CVE — Medium

CVE-2025-21854

VendorlinuxProductlinux kernelDiscoveredMar 12, 2025UpdatedOct 1, 2025

In the Linux kernel, the following vulnerability has been resolved: sockmap, vsock: For connectible sockets allow only connected sockmap expects all vsocks to have a transport assigned, which is expressed in vsock_proto::psock_update_sk_prot(). However, there is an edge case where an unconnected (connectible) socket may lose its previously assigned transport. This is handled with a NULL check in the vsock/BPF recv path. Another design detail is that listening vsocks are not supposed to have any transport assigned at all. Which implies they are not supported by the sockmap. But this is complicated by the fact that a socket, before switching to TCP_LISTEN, may have had some transport assigned during a failed connect() attempt. Hence, we may end up with a listening vsock in a sockmap, which…

CVSS v3.1
5.5 MEDIUM
EPSS
0.23%
probability of exploitation in 30 days
CISA KEV
Not listed
no confirmed exploitation reported
News coverage
3
sources referencing this CVE
Related IOCs
0
seen in the same coverage
EPSS Trend
Aug 16, 2026 → Oct 7, 2026
▲ 0.03pp
0.21% → 0.23% over 3 tracked changes
CVSS v3.1 Detail
Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
ConfidentialityNONE
IntegrityNONE
AvailabilityHIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Connections
5 relationships
Timeline
disclosure → media coverage
Mar 12, 2025
Disclosure — published as a CVE record. · last revised by NVD Oct 1, 2025
Aug 19, 2025
ubuntu.com reports: USN-7703-1: Linux kernel vulnerabilities
Aug 20, 2025
ubuntu.com reports: USN-7703-2: Linux kernel vulnerabilities
Aug 26, 2025
ubuntu.com reports: USN-7719-1: Linux kernel (Raspberry Pi Real-time) vulnerabilities