CVE-2026-63830
published 2026-07-19CVE-2026-63830: 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…
PriorityP350critical9.4CVSS 3.1
AVNACLPRNUINSUCHIHAL
EPSS
0.35%
28.0th percentile
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.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < f126eed589eec6f201405abbc398844042ef6d57 | f126eed589eec6f201405abbc398844042ef6d57 |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 31a110642b5fb5e61940cbcfb503445ac4f28017 | 31a110642b5fb5e61940cbcfb503445ac4f28017 |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 9bb86d8184b37503816150c4a6ad3c17dfdbe827 | 9bb86d8184b37503816150c4a6ad3c17dfdbe827 |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 0eb4c16c4adb262763bda870a8ed38a1a9dec7ec | 0eb4c16c4adb262763bda870a8ed38a1a9dec7ec |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < d22cc92bc41290e5783a72375e0843d9435f6001 | d22cc92bc41290e5783a72375e0843d9435f6001 |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 1acdd14c0990dd1cd4b6534f00366d2e6dfce05f | 1acdd14c0990dd1cd4b6534f00366d2e6dfce05f |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 21ed9540a8e1906dfcbc1bb82ba9b4de4fa4bd6d | 21ed9540a8e1906dfcbc1bb82ba9b4de4fa4bd6d |
| linux | linux | >= d3b18ad31f93d0b6bae105c679018a1ba7daa9ca < 406e8a651a7b854c41fecd5117bb282b3a6c2c6b | 406e8a651a7b854c41fecd5117bb282b3a6c2c6b |
| linux | linux_kernel | — | — |
CVSS provenance
nvdv3.19.4CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
vendor_redhat9.4CRITICAL
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
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.
ghsa_unreviewed·2026-07-19
CVE-2026-63830 [CRITICAL] 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.
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[] when
VulDB
Linux Kernel up to 7.1.2 Skmsg sk_msg_xfer state issue
vuldb·2026-07-19
CVE-2026-63830 Linux Kernel up to 7.1.2 Skmsg sk_msg_xfer state issue
A vulnerability described as very critical has been identified in Linux Kernel up to 6.1.176/6.6.143/6.12.94/6.18.37/7.1.2. The affected element is the function sk_msg_xfer of the component Skmsg. Executing a manipulation can lead to state issue.
This vulnerability appears as CVE-2026-63830. The attack may be performed from remote. There is no available exploit.
Red Hat
kernel: net: skmsg: preserve sg.copy across SG transforms
vendor_redhat·2026-07-19·CVSS 9.4
CVE-2026-63830 [CRITICAL] CWE-279 kernel: net: skmsg: preserve sg.copy across SG transforms
kernel: net: skmsg: preserve sg.copy across SG transforms
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 pa
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/0eb4c16c4adb262763bda870a8ed38a1a9dec7echttps://git.kernel.org/stable/c/1acdd14c0990dd1cd4b6534f00366d2e6dfce05fhttps://git.kernel.org/stable/c/21ed9540a8e1906dfcbc1bb82ba9b4de4fa4bd6dhttps://git.kernel.org/stable/c/31a110642b5fb5e61940cbcfb503445ac4f28017https://git.kernel.org/stable/c/406e8a651a7b854c41fecd5117bb282b3a6c2c6bhttps://git.kernel.org/stable/c/9bb86d8184b37503816150c4a6ad3c17dfdbe827https://git.kernel.org/stable/c/d22cc92bc41290e5783a72375e0843d9435f6001https://git.kernel.org/stable/c/f126eed589eec6f201405abbc398844042ef6d57
2026-07-19
Published