Answer in brief
CVE-2026-63830 records a Critical severity (CVSS 9.4) vulnerability in net: skmsg: preserve sg.copy across SG transforms. 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.
CVSS is 9.4. 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.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <f126eed589eec6f201405abbc398844042ef6d57 || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <31a110642b5fb5e61940cbcfb503445ac4f28017 || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <9bb86d8184b37503816150c4a6ad3c17dfdbe827 || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <0eb4c16c4adb262763bda870a8ed38a1a9dec7ec || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <d22cc92bc41290e5783a72375e0843d9435f6001 || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <1acdd14c0990dd1cd4b6534f00366d2e6dfce05f || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <21ed9540a8e1906dfcbc1bb82ba9b4de4fa4bd6d || >=d3b18ad31f93d0b6bae105c679018a1ba7daa9ca <406e8a651a7b854c41fecd5117bb282b3a6c2c6b | f126eed589eec6f201405abbc398844042ef6d57, 31a110642b5fb5e61940cbcfb503445ac4f28017, 9bb86d8184b37503816150c4a6ad3c17dfdbe827, 0eb4c16c4adb262763bda870a8ed38a1a9dec7ec, d22cc92bc41290e5783a72375e0843d9435f6001, 1acdd14c0990dd1cd4b6534f00366d2e6dfce05f, 21ed9540a8e1906dfcbc1bb82ba9b4de4fa4bd6d, 406e8a651a7b854c41fecd5117bb282b3a6c2c6b |
| Linux/Linuxgeneric | 4.20 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: net: skmsg: preserve sg.copy across SG transforms The sk_msg sg.copy bitmap is part of the scatterlist entry ownership state. A set bit tells sk_msg_compute_data_pointers() not to expose the entry through writable BPF ctx->data. This protects entries backed by pages that are not private to the sk_msg, such as splice-backed file page-cache pages. Several sk_msg transform paths move, copy, split, or compact msg->sg.data[] entries without moving the matching sg.copy bit. This can make an externally backed entry arrive at a new slot with a clear copy bit. A later SK_MSG verdict can then expose sg_virt(sge) as writable ctx->data and BPF stores can modify the original page cache. Keep sg.copy synchronized with sg.data[] whenever entries are transferred, shifted, split, or copied into a new sk_msg. Clear the bit when an entry is replaced by a newly allocated private page or freed. This covers the BPF pull/push/pop helpers, sk_msg_shift_left/right(), sk_msg_xfer(), and tls_split_open_record(), including the partial tail entry created during TLS open-record splitting.
Quoted source text, attributed separately from HOL analysis.