Is there a public exploit for CVE-2026-99213?

No public exploit for CVE-2026-99213 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-99213?

CVE-2026-99213 scores CVSS 7.8 (v3.1), rated high. EPSS puts the chance of exploitation in the next 30 days at 0.16%.

7.8 High

In the Linux kernel, the following vulnerability has been resolved: vsock: treat TCPCLOSING as once-established Handle the TCPESTABLISHED…

CVE-2026-99213

In the Linux kernel, the following vulnerability has been resolved: vsock: treat TCPCLOSING as once-established Handle the TCPESTABLISHED -> TCPCLOSING transition on OPRST, which can race with the connect loop. Immediately break and return 0 on ESTABLISHED/CLOSING. The return value of connect() should reflect what happened up to the point the connection was established or failed. Events that occur afterwards must not affect it. E.g. even if OPRW has already set skerr, connect() should still return 0, not ENOBUFS because of it. Adapt the inaccurate comment above signalpending(). Resetting a socket that is still present in connectedtable can lead to memory corruption. The reporter noted lost transports for in-flight skbs, and I have reproduced crashes caused by re-insertion into connectedtable. listadd double add: new=, prev=, next=. kernel BUG at lib/listdebug.c:35! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI Workqueue: vsock-loopback vsockloopbackwork RIP: 0010:listaddvalidorreport+0x11f/0x130 Call Trace: vsockinsertconnected.cold+0xe/0x13 virtiotransportrecvpkt+0x10e9/0x1460 vsockloopbackwork+0x305/0x480 processonework+0xe4c/0x1560 workerthread+0x4f1/0xd60 kthread+0x36e/0x470…

Assessment

CVSS: 7.8 (v3.1)
Severity: High
EPSS: 0.16% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 28 October 2026
Last updated: 31 October 2026
Affected: Linux
Assigner: Linux

CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

At the source

EUVD (ENISA)

References

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