ex_aws_sns SigningCertURL not validated in verify_message/1_CVE-2026-47074

{
    "lastseen": "",
    "description": "Improper Certificate Validation vulnerability in ex-aws ex_aws_sns (ExAws.SNS, ExAws.SNS.PublicKeyCache modules) allows Signature Spoofing by Improper Validation.\n\nThis vulnerability is associated with program files lib/ex_aws/sns.ex, lib/ex_aws/sns/public_key_cache.ex and program routines 'Elixir.ExAws.SNS':verify_message/1, 'Elixir.ExAws.SNS.PublicKeyCache':get/1.\n\n'Elixir.ExAws.SNS':verify_message/1 fetches the signing certificate from the SigningCertURL field of the incoming SNS message without validating that the URL uses HTTPS or that the host matches an AWS-owned SNS certificate domain. An unauthenticated attacker who can POST to an endpoint that calls verify_message/1 can supply an attacker-controlled SigningCertURL, sign a forged SNS message with their own key, and cause the function to return :ok, completely bypassing SNS signature verification.\n\nThis issue affects ex_aws_sns: from 2.0.1 before 2.3.5.",
    "published": "2026-05-28T09:05:54.815Z",
    "modified": "2026-05-28T09:05:54.815Z",
    "type": "cve",
    "title": "ex_aws_sns SigningCertURL not validated in verify_message/1",
    "source": "EEF",
    "references": "https://github.com/ex-aws/ex_aws_sns/security/advisories/GHSA-8jgf-23q5-x7xx\nhttps://cna.erlef.org/cves/CVE-2026-47074.html\nhttps://osv.dev/vulnerability/EEF-CVE-2026-47074\nhttps://github.com/ex-aws/ex_aws_sns/commit/1853d280b152d10384a1e21a22cf22152a60be48",
    "id": "CVE-2026-47074",
    "bulletinFamily": "",
    "cwe": [
        "CWE-295"
    ],
    "cvelist": null,
    "sourceData": "ex-aws ex_aws_sns 2.0.1\nex-aws ex_aws_sns a7ec21880943f4dac1d59bda557db0ffcd2b61fa",
    "sourceHref": "",
    "cvss": {
        "score": 8.7,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
        "version": "4.0"
    },
    "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": "ex_aws_sns",
    "version": "2.0.1",
    "vendor": "ex-aws",
    "ai_description": "Improper Certificate Validation vulnerability allowing Signature Spoofing by Improper Validation",
    "ai_severity": "High",
    "ai_vendor": "ex-aws",
    "ai_product": "ex_aws_sns",
    "ai_version": "2.0.1 to 2.3.4",
    "ai_score": 8.7
}