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                "id": "CVE-2026-110310",
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                "timestamp": "2026-10-14T19:46:05.003309Z",
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
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        {
          "defaultStatus": "unaffected",
          "product": "Amazon.Extensions.S3.Encryption",
          "vendor": "Amazon",
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              "lessThanOrEqual": "2.*",
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              "value": "\u003cp\u003eA remote user who can read encrypted objects in the S3 bucket can force a padding downgrade by altering the padding scheme recorded in an object\u0027s metadata to legacy PKCS#1 v1.5. Since this padding scheme is susceptible to the well-known Bleichenbacher attack, the user can use a PKCS#1 v1.5 padding oracle to recover the RSA-wrapped envelope key and decrypt the object.\u003c/p\u003e\u003cp\u003eTo remediate this issue, we recommend that users upgrade to version 3.2.2 or 4.0.3. The 1.x and 2.x lines will not be patched, users of those lines need to migrate to 3.2.2 or 4.0.3.\u003c/p\u003e"
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              "lang": "en",
              "value": "CAPEC-463 Padding Oracle Crypto Attack"
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              "description": "CWE-204 Observable response discrepancy",
              "lang": "en",
              "type": "CWE"
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          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-757",
              "description": "CWE-757 Selection of Less-Secure algorithm during negotiation (\u0027algorithm downgrade\u0027)",
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              "type": "CWE"
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        "dateUpdated": "2026-10-14T19:46:28.634Z",
        "orgId": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
        "shortName": "AMZN"
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          "tags": [
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            "patch"
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          "url": "https://www.nuget.org/packages/Amazon.Extensions.S3.Encryption/3.2.2"
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            "patch"
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          "url": "https://www.nuget.org/packages/Amazon.Extensions.S3.Encryption/4.0.3"
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        {
          "tags": [
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          ],
          "url": "https://aws.amazon.com/security/security-bulletins/2026-135-aws/"
        },
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          "tags": [
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          ],
          "url": "https://github.com/aws/amazon-s3-encryption-client-dotnet/security/advisories/GHSA-322w-f6rw-r4fj"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "RSA PKCS#1 v1.5 padding oracle via legacy envelope key format downgrade in Amazon S3 Encryption Client for .NET",
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    "datePublished": "2026-10-14T19:37:48.420Z",
    "dateReserved": "2026-10-13T20:08:06.762Z",
    "dateUpdated": "2026-10-14T19:46:28.634Z",
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