Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0028 20.7 —
AFFECTED
Product Versions Fixed
Linux 012a211abd5db098094ce429de5f046368391e68 – —
Linux 5.9 – 5.10.214
TIMELINE
Feb 19 Reserved by Linux
Apr 17 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2024-26870 (Linux). CVSS 7.8 → 5.5 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102
A call to listxattr() with a buffer size = 0 returns the actual
size of the buffer needed for a subsequent call. When size > 0,
nfs4_listxattr() does not return an error because either
generic_listxattr() or nfs4_listxattr_nfs4_label() consumes
exactly all the bytes then size is 0 when calling
nfs4_listxattr_nfs4_user() which then triggers the following
kernel BUG:
[ 99.403778] kernel BUG at mm/usercopy.c:102!
[ 99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[ 99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1
[ 99.415827] Call trace:
[ 99.415985] usercopy_abort+0x70/0xa0
[ 99.416227] __check_heap_object+0x134/0x158
[ 99.416505] check_heap_object+0x150/0x188
[ 99.416696] __check_object_size.part.0+0x78/0x168
[ 99.416886] __check_object_size+0x28/0x40
[ 99.417078] listxattr+0x8c/0x120
[ 99.417252] path_listxattr+0x78/0xe0
[ 99.417476] __arm64_sys_listxattr+0x28/0x40
[ 99.417723] invoke_syscall+0x78/0x100
[ 99.417929] el0_svc_common.constprop.0+0x48/0xf0
[ 99.418186] do_el0_svc+0x24/0x38
[ 99.418376] el0_svc+0x3c/0x110
[ 99.418554] el0t_64_sync_handler+0x120/0x130
[ 99.418788] el0t_64_sync+0x194/0x198
[ 99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)
Issue is reproduced when generic_listxattr() returns 'system.nfs4_acl',
thus calling lisxattr() with size = 16 will trigger the bug.
Add check on nfs4_listxattr() to return ERANGE error when it is
called with size > 0 and the return value is greater than size.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| February 19, 2024 | Reserved | Reserved by Linux |
| April 17, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2024-26870 (Linux). CVSS 7.8 → 5.5 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 012a211abd5db098094ce429de5f046368391e68 | — |
| Linux | Linux | — | 5.9 | 5.10.214 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2024-26870 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.