{"id":"AZL-71396","summary":"CVE-2025-40248 affecting package kernel for versions less than 6.6.119.3-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvsock: Ignore signal/timeout on connect() if already established\n\nDuring connect(), acting on a signal/timeout by disconnecting an already\nestablished socket leads to several issues:\n\n1. connect() invoking vsock_transport_cancel_pkt() -\u003e\n   virtio_transport_purge_skbs() may race with sendmsg() invoking\n   virtio_transport_get_credit(). This results in a permanently elevated\n   `vvs-\u003ebytes_unsent`. Which, in turn, confuses the SOCK_LINGER handling.\n\n2. connect() resetting a connected socket's state may race with socket\n   being placed in a sockmap. A disconnected socket remaining in a sockmap\n   breaks sockmap's assumptions. And gives rise to WARNs.\n\n3. connect() transitioning SS_CONNECTED -\u003e SS_UNCONNECTED allows for a\n   transport change/drop after TCP_ESTABLISHED. Which poses a problem for\n   any simultaneous sendmsg() or connect() and may result in a\n   use-after-free/null-ptr-deref.\n\nDo not disconnect socket on signal/timeout. Keep the logic for unconnected\nsockets: they don't linger, can't be placed in a sockmap, are rejected by\nsendmsg().\n\n[1]: https://lore.kernel.org/netdev/e07fd95c-9a38-4eea-9638-133e38c2ec9b@rbox.co/\n[2]: https://lore.kernel.org/netdev/20250317-vsock-trans-signal-race-v4-0-fc8837f3f1d4@rbox.co/\n[3]: https://lore.kernel.org/netdev/60f1b7db-3099-4f6a-875e-af9f6ef194f6@rbox.co/","modified":"2026-04-01T05:20:44.282388Z","published":"2025-12-04T16:16:18Z","upstream":["CVE-2025-40248"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40248"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.119.3-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-71396.json"}}],"schema_version":"1.7.5"}