CVE-2026-98119

Medium

Description

In the Linux kernel, the following vulnerability has been resolved: netfs: break unbuffered write when netfs_alloc_subrequest() fails syzbot reported a null-ptr-deref below [1] following a fault injection in netfs_alloc_subrequest(). [0] When netfs_alloc_subrequest() fails, subreq is NULL. Later, netfs_prepare_write() tries to initialize members of subreq(e.g., source), the issue in [1] is triggered. Let's handle the error of netfs_prepare_write() properly. [0] FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 Call Trace: netfs_alloc_subrequest+0x116/0x3f0 netfs_prepare_write+0x76/0x7b0 netfs_unbuffered_write+0x75c/0x2020 netfs_unbuffered_write_iter_locked+0x7d6/0xa80 netfs_unbuffered_write_iter+0x442/0x720 v9fs_file_write_iter+0xbf/0x100 vfs_write+0x6ac/0x1050 [1] KASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af] RIP: 0010:netfs_prepare_write+0xbc/0x7b0 fs/netfs/write_issue.c:173 Call Trace: netfs_unbuffered_write+0x75c/0x2020 fs/netfs/direct_write.c:111 netfs_unbuffered_write_iter_locked+0x7d6/0xa80 fs/netfs/direct_write.c:290 netfs_unbuffered_write_iter+0x442/0x720 fs/netfs/direct_write.c:382 v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:409 new_sync_write fs/read_write.c:595 [inline]

SeverityMedium
CVSS5.5
Exploit probability—
ProductLinux Kernel
PublishedSep 25, 2026
First seenSep 25, 2026

How to fix

Update
  • linux linux_kernel6.18.53, 7.2.7 or later

Affected products

ProductAffected versionsFixed in
linux linux_kernel6.10 ≤ v < 6.18.53, 6.19 ≤ v < 7.2.7, 7.36.18.53, 7.2.7

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.