Key commitment policy bypass via shared key cache in AWS Encryption SDK for Python_CVE-2026-6550

{
    "lastseen": "",
    "description": "Cryptographic algorithm downgrade in the caching layer of Amazon AWS Encryption SDK for Python before version 3.3.1 and before version  4.0.5 might allow an authenticated local threat actor to bypass key commitment policy enforcement via a shared key cache, resulting in ciphertext that can be decrypted to multiple different plaintexts.\n\nTo remediate this issue, users should upgrade to version 3.3.1, 4.0.5 or above.",
    "published": "2026-04-20T19:20:23.383Z",
    "modified": "2026-04-20T19:44:11.685Z",
    "type": "cve",
    "title": "Key commitment policy bypass via shared key cache in AWS Encryption SDK for Python",
    "source": "AMZN",
    "references": "https://aws.amazon.com/security/security-bulletins/2026-017-aws/\nhttps://github.com/aws/aws-encryption-sdk-python/releases/tag/v4.0.5\nhttps://github.com/aws/aws-encryption-sdk-python/releases/tag/v3.3.1\nhttps://github.com/aws/aws-encryption-sdk-python/security/advisories/GHSA-v638-38fc-rhfv",
    "id": "CVE-2026-6550",
    "bulletinFamily": "",
    "cwe": [
        "CWE-757"
    ],
    "cvelist": null,
    "sourceData": "AWS AWS Encryption SDK for Python 2\nAWS AWS Encryption SDK for Python 3\nAWS AWS Encryption SDK for Python 4",
    "sourceHref": "",
    "cvss": {
        "score": 4.7,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "AWS Encryption SDK for Python",
    "version": "2",
    "vendor": "AWS",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}