SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2022-50747

In the Linux kernel, the following vulnerability has been resolved: hfs: Fix OOB Write in hfs_asc2mac Syzbot reported a OOB Write bug: loop0: detected capacity change from 0 to 64 ================================================================== BUG:…

HIGH 7.8EPSS 0.21%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.21%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

In the Linux kernel, the following vulnerability has been resolved: hfs: Fix OOB Write in hfs_asc2mac Syzbot reported a OOB Write bug: loop0: detected capacity change from 0 to 64 ================================================================== BUG: KASAN: slab-out-of-bounds in hfs_asc2mac+0x467/0x9a0 fs/hfs/trans.c:133 Write of size 1 at addr ffff88801848314e by task syz-executor391/3632 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 print_address_description+0x74/0x340 mm/kasan/report.c:284 print_report+0x107/0x1f0 mm/kasan/report.c:395 kasan_report+0xcd/0x100 mm/kasan/report.c:495 hfs_asc2mac+0x467/0x9a0 fs/hfs/trans.c:133 hfs_cat_build_key+0x92/0x170 fs/hfs/catalog.c:28 hfs_lookup+0x1ab/0x2c0 fs/hfs/dir.c:31 lookup_open fs/namei.c:3391 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x10e6/0x2df0 fs/namei.c:3710 do_filp_open+0x264/0x4f0 fs/namei.c:3740 If in->len is much larger than HFS_NAMELEN(31) which is the maximum length of an HFS filename, a OOB write could occur in hfs_asc2mac(). In that case, when the dst reaches the boundary, the srclen is still greater than 0, which causes a OOB write. Fix this by adding a check on dstlen in while() before writing to dst address.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.21% probability · 11th percentile
CISA KEV
Not listed
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.