bouncycastle security update

{
  "id": "2a79e9600661b7804a1f57aa65817d037cf96ba3a650a6a0072cb4838404c338",
  "url": "https://osv.dev/vulnerability/OESA-2026-4243",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "bouncycastle security update",
    "summary": "The package is organised so that it contains a light-weight API suitable for use in any environment (including the newly released J2ME) with the additional infrastructure to conform the algorithms to the JCE framework. Security Fix(es): In Bouncy Castle for Java before 1.86, the streaming CMS AuthenticatedData parser accepted a message whose digestAlgorithm and authAttrs fields disagreed about whether authenticated attributes were present. RFC 5652 sec. 9.1 pairs the two, requiring that authAttrs be present whenever digestAlgorithm is, and sec. 9.2 makes the MAC cover the DER encoding of authAttrs when they are present and the eContent OCTET STRING directly when they are not. CMSAuthenticatedDataParser has to choose between those two in its constructor, before it can reach authAttrs, which comes later in the SEQUENCE, so it chose on digestAlgorithm alone: for a message with digestAlgorithm absent but authAttrs present it verified the content MAC and then returned the attributes through getAuthAttrs() as though they had been authenticated, when the MAC had never covered them. An attacker able to modify a message in transit could insert an authenticated attribute, such as an RFC 2634 ESSSecurityLabel, into an otherwise valid message while holding neither the key-encryption key nor the content-MAC key, and an application taking an authorization, routing or labelling decision from those attributes would act on attacker-chosen values. The content itself remained MAC-bound. asn1.cm",
    "evidence": "osv:OESA-2026-4243",
    "products": [
      {
        "name": {
          "value": "bouncycastle",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.67-3.oe2203sp4",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "OESA-2026-4243",
      "aliases": [
        "OESA-2026-4243"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "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"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1.67-3.oe2203sp4"
                }
              ]
            }
          ],
          "package": {
            "name": "bouncycastle",
            "purl": "pkg:rpm/openEuler/bouncycastle&distro=openEuler-22.03-LTS-SP4",
            "ecosystem": "openEuler:22.03-LTS-SP4"
          },
          "database_specific": {
            "source": "https://repo.openeuler.org/security/data/osv/OESA-2026-4243.json"
          },
          "ecosystem_specific": {
            "src": [
              "bouncycastle-1.67-3.oe2203sp4.src.rpm"
            ],
            "noarch": [
              "bouncycastle-1.67-3.oe2203sp4.noarch.rpm"
            ]
          }
        }
      ],
      "modified": "2026-10-16T12:15:04.192725634Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-71888"
      ],
      "references": [
        "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4243",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-71888"
      ],
      "provider_metadata": {
        "severity": "High"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-71888",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 340744,
  "published_at": "2026-10-16T11:58:32+00:00"
}