CVE-2026-72222: sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.6%
EPSS score, percentile 50.3 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 6.4
Unaffected before 6.4; 6.6.145; 6.12.97; 6.18.40; 7.1.5; 7.2
Source: CISA KEV 2026.10.28, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from b3cbf98e2fdf to before f3b55945dd99 |
| Affected | from b3cbf98e2fdf to before 2d4f97d13fff |
| Affected | from b3cbf98e2fdf to before 3f9ee75a97a7 |
| Affected | from b3cbf98e2fdf to before 083e9c2ec7e8 |
| Affected | from b3cbf98e2fdf to before 4f988f3a2808 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 6.4 |
| Unaffected | before 6.4 |
| Unaffected | 6.6.145 |
| Unaffected | 6.12.97 |
| Unaffected | 6.18.40 |
| Unaffected | 7.1.5 |
| Unaffected | 7.2 |
Versions not listed are: affected.
Versions the record lists as unaffected: 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2.
Source: CVE List, as of . About the data.
About this vulnerability
In the Linux kernel, the following vulnerability has been resolved: sunrpc: pin svc_xprt across the asynchronous TLS handshake callback svc_tcp_handshake() stores the raw svc_xprt pointer in tls_handshake_args.ta_data and submits the request through tls_server_hello_x509(). The handshake core takes only sock_hold(req->hr_sk); nothing references the embedding struct svc_sock that svc_tcp_handsha…
Summary: CVE record, as of .
- CISA has not added CVE-2026-72222 to its Known Exploited Vulnerabilities (KEV) catalog, as of 28 Oct 2026.
- The CVE record was published on 15 Aug 2026.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.6% (percentile 50.3), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
Source: CISA KEV 2026.10.28, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
In the Linux kernel, the following vulnerability has been resolved: sunrpc: pin svc_xprt across the asynchronous TLS handshake callback svc_tcp_handshake() stores the raw svc_xprt pointer in tls_handshake_args.ta_data and submits the request through tls_server_hello_x509(). The handshake core takes only sock_hold(req->hr_sk); nothing references the embedding struct svc_sock that svc_tcp_handshake_done() reaches via container_of(). Two close races leave the in-flight callback writing through a freed svc_sock. svc_sock_free() calls tls_handshake_cancel() and discards its return value: a false return means handshake_complete() has already set HANDSHAKE_F_REQ_COMPLETED but hp_done() may not have finished, yet svc_sock_free() proceeds to kfree(svsk). The cancel-loser fall-through inside svc_tcp_handshake() itself produces the same window: when wait_for_completion_interruptible_timeout() returns <= 0 (timeout or signal) and tls_handshake_cancel() returns false, the function does not drain, returns, and svc_handle_xprt() calls svc_xprt_received(), which clears XPT_BUSY and can drop the last reference. A concurrent close then runs svc_sock_free() while svc_tcp_handshake_done() is still updating xpt_flags and walking svsk->sk_handshake_done. The corruption surfaces as set_bit/clear_bit RMW into the freed xpt_flags slab slot and as complete_all() walking and writing the freed wait_queue_head_t list embedded in sk_handshake_done -- a slab-corruption primitive, not a benign read. The path is reachable on any TLS-enabled NFS server whenever a connection close overlaps the tlshd downcall delivery window; the interruptible wait means signal delivery suffices, not just SVC_HANDSHAKE_TO expiry. Take svc_xprt_get(xprt) immediately before tls_server_hello_x509() so the in-flight callback owns its own reference. Release it on the two edges where the callback is guaranteed not to fire -- submission failure from tls_server_hello_x509() and a successful tls_handshake_cancel() -- and at the tail of svc_tcp_handshake_done() after complete_all(). [cel: rewrote commit message to describe the actual change]
Source: CVE List, as of . About the data.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
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