CVE-2026-55392

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nilfs-dev/nilfs-utils/commit/26efb5daff0757365101035145331b0a5a85d9d9
https://github.com/nilfs-dev/nilfs-utils/issues/26

Configurations

No configuration.

History

18 Jun 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-18 19:16

Updated : 2026-06-18 20:16

NVD link : CVE-2026-55392

Mitre link : CVE-2026-55392

CVE.ORG link : CVE-2026-55392

JSON object : View

Products Affected

No product.

CWE

CWE-1284

Improper Validation of Specified Quantity in Input

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