7.1

CVE-2022-50478: nilfs2: fix shift-out-of-bounds/overflow in nilfs_sb2_bad_offset()

Analyzed
AliasesUBUNTU-CVE-2022-50478DEBIAN-CVE-2022-50478
Published 04-10-2025Last modified 11-05-2026

Vulnerability summary

CVE-2022-50478 is a high (CVSS 7.1) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.4% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.1, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.1/10
010
High · v3.1 (NVD)
EPSS score
0.17%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 4 · Related 4
SUSE-SU-2025:4111-1SUSE-SU-2025:4139-1SUSE-SU-2025:4149-1SUSE-SU-2025:4320-1

Timeline

  1. 04-10-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix shift-out-of-bounds/overflow in nilfs_sb2_bad_offset() Patch series "nilfs2: fix UBSAN shift-out-of-bounds warnings on mount time". The first patch fixes a bug reported by syzbot, and the second one fixes the remaining bug of the same kind. Although they are triggered by the same super block data anomaly, I divided it into the above two because the details of the issues and how to fix it are different. Both are required to eliminate the shift-out-of-bounds issues at mount time. This patch (of 2): If the block size exponent information written in an on-disk superblock is corrupted, nilfs_sb2_bad_offset helper function can trigger shift-out-of-bounds warning followed by a kernel panic (if panic_on_warn is set): shift exponent 38983 is too large for 64-bit type 'unsigned long long' Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 ubsan_epilogue lib/ubsan.c:151 [inline] __ubsan_handle_shift_out_of_bounds+0x33d/0x3b0 lib/ubsan.c:322 nilfs_sb2_bad_offset fs/nilfs2/the_nilfs.c:449 [inline] nilfs_load_super_block+0xdf5/0xe00 fs/nilfs2/the_nilfs.c:523 init_nilfs+0xb7/0x7d0 fs/nilfs2/the_nilfs.c:577 nilfs_fill_super+0xb1/0x5d0 fs/nilfs2/super.c:1047 nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1317 ... In addition, since nilfs_sb2_bad_offset() performs multiplication without considering the upper bound, the computation may overflow if the disk layout parameters are not normal. This fixes these issues by inserting preliminary sanity checks for those parameters and by converting the comparison from one involving multiplication and left bit-shifting to one using division and right bit-shifting.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.17%

Chance of exploitation in the next 30 days

Percentile

6%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.17% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu121 products
  • linuxAll versions (No fix recorded) | < 4.15.0-208.220 | < 5.4.0-144.161 | < 5.15.0-69.76
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 4.15.0-1153.166 | < 5.4.0-1097.105 | < 5.15.0-1033.37
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < 6b0ea3df56cccd53398d0289f399f19d43136b2e | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < a6f89b10042baca218c8598d6db5a44c7e32625f | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < 9b3ba54025357440d6c4414c670984f628c6f6bf | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < d706485dffbbbf848e681edda29c7a46ac55698c | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < d464b035c0613856d012cf1704879d3ff3f057fb | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < b47f5c579c8186f7f5ab5e4254e0734ea5b7bf7a | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < 1012ff77284e3bec0ec0a35a820b03ec43dec2cc | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < 62d11ec205ef14d8acf172cfc9904fdbf200025a | ≥ e339ad31f59925b48a92ee3947692fdf9758b8c7, < 610a2a3d7d8be3537458a378ec69396a76c385b6 | 2.6.30
  • linux_kernel≥ 2.6.30, < 4.9.337 | ≥ 4.10, < 4.14.303 | ≥ 4.15, < 4.19.270 | ≥ 4.20, < 5.4.229 | ≥ 5.5, < 5.10.163 | ≥ 5.11, < 5.15.86 | ≥ 5.16, < 6.0.16 | ≥ 6.1, < 6.1.2
Debian1 product
  • linux< 6.1.4-1

3 vendors · 124 products

References

13 links
Show all 13 references