USN-5168-4 (UBUNTU-CVE-2021-43527)

Vulnerability from osv_ubuntu – Published: 2021-12-07 19:35 – Updated: 2026-06-29 10:52 – Source website
VLAI
Summary
nss regression
Details

USN-5168-3 fixed a vulnerability in NSS. Unfortunately that update introduced a regression that could break SSL connections. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Tavis Ormandy discovered that NSS incorrectly handled verifying DSA/RSA-PSS signatures. A remote attacker could use this issue to cause NSS to crash, resulting in a denial of service, or possibly execute arbitrary code.

References
To clipboard 

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      "database_specific": {
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          "cves": [
            {
              "id": "CVE-2021-43527",
              "severity": [
                {
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                  "type": "CVSS_V3"
                },
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                  "score": "high",
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        }
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          {
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      },
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        "name": "nss",
        "purl": "pkg:deb/ubuntu/nss@2:3.28.4-0ubuntu0.14.04.5+esm10?arch=source\u0026distro=trusty/esm"
      },
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          "type": "ECOSYSTEM"
        }
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      ]
    },
    {
      "database_specific": {
        "cves_map": {
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              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "high",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libnss3",
            "binary_version": "2:3.28.4-0ubuntu0.16.04.14+esm2"
          },
          {
            "binary_name": "libnss3-1d",
            "binary_version": "2:3.28.4-0ubuntu0.16.04.14+esm2"
          },
          {
            "binary_name": "libnss3-nssdb",
            "binary_version": "2:3.28.4-0ubuntu0.16.04.14+esm2"
          },
          {
            "binary_name": "libnss3-tools",
            "binary_version": "2:3.28.4-0ubuntu0.16.04.14+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "nss",
        "purl": "pkg:deb/ubuntu/nss@2:3.28.4-0ubuntu0.16.04.14+esm2?arch=source\u0026distro=esm-infra/xenial"
      },
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2:3.19.2-1ubuntu1",
        "2:3.19.2.1-0ubuntu1",
        "2:3.21-1ubuntu2",
        "2:3.21-1ubuntu3",
        "2:3.21-1ubuntu4",
        "2:3.23-0ubuntu0.16.04.1",
        "2:3.26.2-0ubuntu0.16.04.2",
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        "2:3.28.4-0ubuntu0.16.04.14+esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-5168-3 fixed a vulnerability in NSS. Unfortunately that update introduced\na regression that could break SSL connections. This update fixes the problem.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n Tavis Ormandy discovered that NSS incorrectly handled verifying DSA/RSA-PSS\n signatures. A remote attacker could use this issue to cause NSS to crash,\n resulting in a denial of service, or possibly execute arbitrary code.\n \n",
  "id": "USN-5168-4",
  "modified": "2026-06-29T10:52:52Z",
  "published": "2021-12-07T19:35:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5168-4"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-43527"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "nss regression",
  "upstream": [
    "UBUNTU-CVE-2021-43527"
  ]
}



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