Answer in brief
CVE-2026-98253 records a Unknown severity vulnerability in RDMA/ucma: Serialize join and leave on copy_to_user failure. The current sources do not mark it as known exploited. The current feed maps 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.
A CVSS score is not reported in the current record. 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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=60d613b39e8d0c9f3b526e9c96445422b4562d76 <29b9ed83d8bfab5c6e11fcbf1aa836aa4ae26cb9 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <52172e11bd074ccaded21740ffeb67123f01dd00 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <01e29d0d78a8f66f221625720a04939eef5ec1f6 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <ae805d204cf1f15b87d1bf3529b4c649f3519420 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <43c4e24bd10370fc976f6220518049ce71419399 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <01cbdb724c584d7772fd25af2e4dfdf8527ce0d5 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <83610ee5e498fa5bfcb80031d2b959baea276bf6 || >=fe454dc31e84f8c14cb8942fcb61666c9f40745b <662ade4de9ff5eceb0820a9f8e9fac70ba6a815b || a3262b3884dd67b4c5632ce7cdf9cff9d1a575d4 || >=5.10.20 <5.10.271 || >=5.11.3 <5.12 | 29b9ed83d8bfab5c6e11fcbf1aa836aa4ae26cb9, 52172e11bd074ccaded21740ffeb67123f01dd00, 01e29d0d78a8f66f221625720a04939eef5ec1f6, ae805d204cf1f15b87d1bf3529b4c649f3519420, 43c4e24bd10370fc976f6220518049ce71419399, 01cbdb724c584d7772fd25af2e4dfdf8527ce0d5, 83610ee5e498fa5bfcb80031d2b959baea276bf6, 662ade4de9ff5eceb0820a9f8e9fac70ba6a815b, 5.10.271, 5.12 |
| Linux/Linuxgeneric | 5.12 | Not reported |
Published upstream
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 6, 2026
In the Linux kernel, the following vulnerability has been resolved: RDMA/ucma: Serialize join and leave on copy_to_user failure rdma_join_multicast() queues RoCE work that later reads the ucma_multicast through event->param.ud.private_data, then list_add()s the CMA multicast at the head of id_priv->mc_list. rdma_leave_multicast() matches only by sockaddr and destroys the first hit. ucma_process_join() used to drop ctx->mutex after a successful join and retake it only if copy_to_user() failed. Two concurrent JOIN_MCAST calls with the same address can therefore insert a second CMA entry before the first thread's leave. leave then cancels the newer work and the older worker still dereferences the ucma_multicast that the first thread frees. Keep ctx->mutex held from rdma_join_multicast() through copy_to_user() and, on -EFAULT, through rdma_leave_multicast() so leave cannot miss this join. Do not leave if join itself failed: that path never published this address on mc_list, and a leave-by-addr would destroy an earlier successful join.
Quoted source text, attributed separately from HOL analysis.