CVE-2026-55392

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Source
https://cve.org/CVERecord?id=CVE-2026-55392
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55392.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-55392
Downstream
AZL (1)
DEBIAN (1)
MGASA (1)
OESA (4)
openSUSE (2)
UBUNTU (1)
Related
openSUSE (2)
Published
2026-06-18T18:00:12Z
Modified
2026-08-12T16:41:19Z
Severity
  • 6.7 (Medium) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
NILFS utilities - Undefined Behavior and Out-of-Memory via Unvalidated s_log_block_size
Details

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.

Database specific 
{
    "cna_assigner":  "VulnCheck",
    "cwe_ids":  [
        "CWE-1284"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55392.json"
}
References

Affected packages

Git / github.com/nilfs-dev/nilfs-utils

Affected ranges

Type
GIT
Repo
https://github.com/nilfs-dev/nilfs-utils
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
4115aebf9fe29b78caecb7ee8a379390537a0a76
Fixed
26efb5daff0757365101035145331b0a5a85d9d9
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "0"
        },
        {
            "fixed":  "2.3.0"
        }
    ],
    "source":  [
        "DESCRIPTION",
        "REFERENCES"
    ]
}

Affected versions

v2.*
v2.0.0
v2.0.1
v2.0.10
v2.0.11
v2.0.12
v2.0.13
v2.0.14
v2.0.15
v2.0.16
v2.0.17
v2.0.18
v2.0.19
v2.0.2
v2.0.20
v2.0.21
v2.0.22
v2.0.23
v2.0.3
v2.0.4
v2.0.5
v2.0.6
v2.0.7
v2.0.8
v2.0.9
v2.1.0
v2.1.0-rc1
v2.1.0-rc2
v2.1.1
v2.1.2
v2.1.3
v2.1.4
v2.1.5
v2.1.6
v2.2.0
v2.2.1
v2.2.2
v2.2.3
v2.2.4
v2.2.5
v2.3.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55392.json"
vanir_signatures 
[
    {
        "deprecated":  false,
        "digest":  {
            "line_hashes":  [
                "139429108555604321755893781337324730698",
                "290071847760145223543359583221887599697",
                "248067144152988933005337506338606647165",
                "236176387179303495011254244390291711421"
            ],
            "threshold":  0.9
        },
        "id":  "CVE-2026-55392-29dcb09f",
        "signature_type":  "Line",
        "signature_version":  "v1",
        "source":  "https://github.com/nilfs-dev/nilfs-utils/commit/26efb5daff0757365101035145331b0a5a85d9d9",
        "target":  {
            "file":  "lib/sb.c"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "function_hash":  "176752800563585648743943259965792844133",
            "length":  316
        },
        "id":  "CVE-2026-55392-2a8dffb0",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/nilfs-dev/nilfs-utils/commit/26efb5daff0757365101035145331b0a5a85d9d9",
        "target":  {
            "file":  "lib/sb.c",
            "function":  "nilfs_sb_is_valid"
        }
    }
]
vanir_signatures_modified 
"2026-08-12T16:41:19Z"