Answer in brief
CVE-2026-89702 records a Critical severity (CVSS 9.8) vulnerability in nfsd: size fh_verify server sockaddr slot by xpt_locallen. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=051382885552e12541cc0ebf82092be374a9ed2a <95d064f9828a20ccca5ae90a17be3e2076f25272 || >=051382885552e12541cc0ebf82092be374a9ed2a <7ff8d6363cffff45654ea85e319f7c0c54226012 || >=051382885552e12541cc0ebf82092be374a9ed2a <719a10e3f5f868c3c4ac3cf3648c5775d12034bd || >=051382885552e12541cc0ebf82092be374a9ed2a <71d068490098b1d23c63b2345e40675d3a1ca763 || dcbebc86850324fbe0a993ce352f0539cd98038a || 62980365d6e894234b29f44fb2bfad4f7f8bb824 || >=5.15.154 <5.16 | 95d064f9828a20ccca5ae90a17be3e2076f25272, 7ff8d6363cffff45654ea85e319f7c0c54226012, 719a10e3f5f868c3c4ac3cf3648c5775d12034bd, 71d068490098b1d23c63b2345e40675d3a1ca763, 5.16 |
| Linux/Linuxgeneric | 6.0 | Not reported |
| Linux/Linuxgeneric | >=051382885552e12541cc0ebf82092be374a9ed2a <1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5 || >=051382885552e12541cc0ebf82092be374a9ed2a <95d064f9828a20ccca5ae90a17be3e2076f25272 || >=051382885552e12541cc0ebf82092be374a9ed2a <7ff8d6363cffff45654ea85e319f7c0c54226012 || >=051382885552e12541cc0ebf82092be374a9ed2a <719a10e3f5f868c3c4ac3cf3648c5775d12034bd || >=051382885552e12541cc0ebf82092be374a9ed2a <71d068490098b1d23c63b2345e40675d3a1ca763 || dcbebc86850324fbe0a993ce352f0539cd98038a || 62980365d6e894234b29f44fb2bfad4f7f8bb824 || >=5.15.154 <5.16 | 1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5, 95d064f9828a20ccca5ae90a17be3e2076f25272, 7ff8d6363cffff45654ea85e319f7c0c54226012, 719a10e3f5f868c3c4ac3cf3648c5775d12034bd, 71d068490098b1d23c63b2345e40675d3a1ca763, 5.16 |
Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 11, 2026
In the Linux kernel, the following vulnerability has been resolved: nfsd: size fh_verify server sockaddr slot by xpt_locallen The nfsd_fh_verify and nfsd_fh_verify_err tracepoints declare the server sockaddr slot sized by xpt_remotelen but fill it from xpt_local using xpt_locallen: TP_STRUCT__entry( ... __sockaddr(server, rqstp->rq_xprt->xpt_remotelen) ... ) TP_fast_assign( ... __assign_sockaddr(server, &rqstp->rq_xprt->xpt_local, rqstp->rq_xprt->xpt_locallen); ... ) When xpt_locallen exceeds xpt_remotelen, __assign_sockaddr's memcpy writes past the reserved ring-buffer slot. In the reverse direction (xpt_locallen < xpt_remotelen) the slot is oversized and the unwritten tail leaks prior ring-buffer contents to trace consumers. The write-past-end case is reachable on NFS/UDP. svc_xprt_set_remote() is only called from svc_tcp_accept() (net/sunrpc/svcsock.c) and from the RDMA connect path; svc_create_socket() for UDP calls only svc_xprt_set_local(), so xpt_remotelen stays 0 for the xprt's lifetime. Every fh_verify trace for an NFSv2/v3-over-UDP request then copies 16 or 28 bytes from xpt_local into a zero-byte slot. The other NFSD tracepoints that record the server address (NFSD_TRACE_PROC_CALL_FIELDS, NFSD_TRACE_PROC_RES_FIELDS, SVC_RQST_ENDPOINT_FIELDS) already size the server slot by xpt_locallen; nfsd_fh_verify and nfsd_fh_verify_err were the only exceptions. Fix by sizing the server slot with xpt_locallen so the declared slot matches the copy length. The client slot and its assignment already agree on xpt_remotelen and are left untouched.
Quoted source text, attributed separately from HOL analysis.