CVE-2026-54522

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Source
https://cve.org/CVERecord?id=CVE-2026-54522
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54522.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-54522
Aliases
Downstream
Related
Published
2026-07-30T16:33:06.080Z
Modified
2026-08-12T16:41:18.513154Z
Severity
  • 2.1 (Low) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
MessagePack::Buffer#clear Use-After-Free that Enables Cross-Buffer Disclosure
Details

MessagePack for Ruby is an implementation of the MessagePack binary serialization format. Prior to 1.8.2, MessagePack::Buffer#clear in ext/msgpack/buffer.c leaves rmemlast, rmemend, and rmemowner stale after msgpackbuffershift_chunk returns an rmem page to the shared pool, allowing a subsequent Buffer#write and a second MessagePack::Buffer to alias the page and disclose or corrupt cross-buffer data. This issue is fixed in version 1.8.2.

Database specific 
{
    "cwe_ids": [
        "CWE-416"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54522.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/msgpack/msgpack-ruby

Affected ranges

Type
GIT
Repo
https://github.com/msgpack/msgpack-ruby
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
09c914d75f296d6edb9fadb65b9ad614eb0bbfc7
Fixed
5627d71606b565641d2dd501b82aae862f4abe90
Database specific
Show details 
{
    "cpe": "cpe:2.3:a:msgpack:messagepack:*:*:*:*:*:ruby:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.8.2"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

Affected versions

v0.*
v0.5.0
v0.5.1
v0.5.10
v0.5.11
v0.5.2
v0.5.3
v0.5.4
v0.5.5
v0.5.6
v0.5.7
v0.5.8
v0.5.9
v0.6.0
v0.6.0pre1
v0.6.1
v0.6.2
v0.7.0
v0.7.1
v0.7.2
v0.7.3
v0.7.4
v0.7.5
v0.7.6
v1.*
v1.0.0
v1.0.1
v1.0.2
v1.0.3
v1.1.0
v1.2.0
v1.2.1
v1.2.10
v1.2.2
v1.2.3
v1.2.4
v1.2.5
v1.2.6
v1.2.7
v1.2.8
v1.2.9
v1.3.0
v1.3.1
v1.3.2
v1.3.3
v1.4.0
v1.4.1
v1.4.2
v1.4.3
v1.4.4
v1.4.5
v1.5.0
v1.5.1
v1.5.2
v1.5.3
v1.5.4
v1.5.5
v1.5.6
v1.6.0
v1.6.1
v1.7.0
v1.7.1
v1.7.2
v1.7.3
v1.7.4
v1.7.5
v1.8.0
v1.8.1

Database specific

vanir_signatures_modified 
"2026-08-12T16:41:18Z"
vanir_signatures 
[
    {
        "id": "CVE-2026-54522-0c48a748",
        "deprecated": false,
        "signature_type": "Line",
        "signature_version": "v1",
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "62515399619151110189481082912345304106",
                "157328647613235767233816264595413167422",
                "82844948022617087820993061839250164793",
                "82217288161328941814490663109635154035"
            ]
        },
        "source": "https://github.com/msgpack/msgpack-ruby/commit/5627d71606b565641d2dd501b82aae862f4abe90",
        "target": {
            "file": "ext/msgpack/buffer.c"
        }
    },
    {
        "id": "CVE-2026-54522-4de75f32",
        "deprecated": false,
        "signature_type": "Function",
        "signature_version": "v1",
        "digest": {
            "length": 382.0,
            "function_hash": "111911793690646822479415364421376939223"
        },
        "source": "https://github.com/msgpack/msgpack-ruby/commit/5627d71606b565641d2dd501b82aae862f4abe90",
        "target": {
            "function": "_msgpack_buffer_shift_chunk",
            "file": "ext/msgpack/buffer.c"
        }
    }
]
source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54522.json"