CVE-2026-56099

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Source
https://cve.org/CVERecord?id=CVE-2026-56099
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56099.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-56099
Published
2026-06-18T19:29:08Z
Modified
2026-10-21T10:24:40Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
OpenBSD mpls_do_error Kernel Stack Memory Disclosure via MPLS Input
Details

OpenBSD before commit 6a23123 (2026-06-18) contains an out-of-bounds read vulnerability in the mpls_do_error function within sys/netmpls/mpls_input.c that allows remote attackers to disclose kernel stack memory by sending crafted MPLS frames with 16 labels and no Bottom-of-Stack bit set.

Database specific 
{
    "cna_assigner":  "VulnCheck",
    "cwe_ids":  [
        "CWE-125"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56099.json"
}
References

Affected packages

Git / github.com/openbsd/src

Affected ranges

Type
GIT
Repo
https://github.com/openbsd/src
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd
Database specific
Show details 
{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "fixed":  "6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
                }
            ],
            "source":  "AFFECTED_FIELD",
            "strategy":  "StandardRange"
        },
        {
            "range":  [
                {
                    "fixed":  "6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"
                }
            ],
            "source":  "REFERENCES_COMMIT"
        }
    ]
}

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56099.json"
vanir_signatures 
[
    {
        "deprecated":  false,
        "digest":  {
            "line_hashes":  [
                "214501725817765619687789676424629373910",
                "171745048645506414789133289662303457947",
                "183165387675308835546541401840556237993",
                "270311563117041349745719620477978035278",
                "335522886547838601549901776027989373454"
            ],
            "threshold":  0.9
        },
        "id":  "CVE-2026-56099-743cd715",
        "signature_type":  "Line",
        "signature_version":  "v1",
        "source":  "https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd",
        "target":  {
            "file":  "sys/netmpls/mpls_input.c"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "function_hash":  "290605894353759007932632249171159928095",
            "length":  2430
        },
        "id":  "CVE-2026-56099-b2790f1d",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd",
        "target":  {
            "file":  "sys/netmpls/mpls_input.c",
            "function":  "mpls_do_error"
        }
    }
]
vanir_signatures_modified 
"2026-10-21T10:24:40Z"