CVE-2026-55392
NILFS utilities - Undefined Behavior and Out-of-Memory via Unvalidated s_log_block_size
Description
NILFS utilities through 2.3.0, fixed in commit 26efb5d, nilfs_sb_is_valid() function fails to validate s_log_block_size field in NILFS2 superblock before bit-shift operations. Attackers supplying crafted NILFS2 images trigger undefined behavior through oversized shifts or out-of-memory conditions, crashing tools like nilfs-tune and dumpseg.
INFO
Published Date :
June 18, 2026, 6 p.m.
Last Modified :
June 18, 2026, 6 p.m.
Remotely Exploit :
No
Source :
VulnCheck
Affected Products
The following products are affected by CVE-2026-55392
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 |
Solution
- Update NILFS utilities to a patched version.
- Apply commit 26efb5d to affected code.
- Validate superblock field values before bit-shift operations.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55392 vulnerability anywhere in the article.