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usn-8712-1
Vulnerability from osv_ubuntu
Published
2026-09-01 16:20
Modified
2026-09-01 16:20
Summary
pyasn1 vulnerabilities
Details

It was discovered that pyasn1 did not properly bound the size of long-form tag identifiers when parsing BER, CER, or DER encoded data. An attacker could possibly use this issue to cause applications decoding untrusted ASN.1 data to consume excessive CPU resources, resulting in a denial of service. (CVE-2026-59884)

It was discovered that pyasn1 processed OBJECT IDENTIFIER and RELATIVE-OID values in quadratic time relative to the number of arcs. An attacker could possibly use this issue to cause applications decoding untrusted ASN.1 data to consume excessive CPU resources, resulting in a denial of service. (CVE-2026-59885)

It was discovered that pyasn1 incorrectly handled conversion of decoded REAL values to Python float types. An attacker could possibly use this issue to cause applications decoding untrusted ASN.1 data to consume excessive CPU and memory resources, resulting in a denial of service. (CVE-2026-59886)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-59884",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59885",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59886",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "pypy-pyasn1",
            "binary_version": "0.4.8-1ubuntu0.3"
          },
          {
            "binary_name": "python3-pyasn1",
            "binary_version": "0.4.8-1ubuntu0.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "pyasn1",
        "purl": "pkg:deb/ubuntu/pyasn1@0.4.8-1ubuntu0.3?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.4.8-1ubuntu0.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.8-1",
        "0.4.8-1ubuntu0.1",
        "0.4.8-1ubuntu0.2"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-59884",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59885",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59886",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-pyasn1",
            "binary_version": "0.4.8-4ubuntu0.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "pyasn1",
        "purl": "pkg:deb/ubuntu/pyasn1@0.4.8-4ubuntu0.3?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.4.8-4ubuntu0.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.8-4",
        "0.4.8-4ubuntu0.1",
        "0.4.8-4ubuntu0.2"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-59884",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59885",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-59886",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-pyasn1",
            "binary_version": "0.6.3-1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "pyasn1",
        "purl": "pkg:deb/ubuntu/pyasn1@0.6.3-1ubuntu0.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.6.3-1ubuntu0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.6.1-1",
        "0.6.1-1build1",
        "0.6.2-1",
        "0.6.3-1"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that pyasn1 did not properly bound the size of long-form\ntag identifiers when parsing BER, CER, or DER encoded data. An attacker\ncould possibly use this issue to cause applications decoding untrusted\nASN.1 data to consume excessive CPU resources, resulting in a denial of\nservice. (CVE-2026-59884)\n\nIt was discovered that pyasn1 processed OBJECT IDENTIFIER and RELATIVE-OID\nvalues in quadratic time relative to the number of arcs. An attacker could\npossibly use this issue to cause applications decoding untrusted ASN.1 data\nto consume excessive CPU resources, resulting in a denial of service.\n(CVE-2026-59885)\n\nIt was discovered that pyasn1 incorrectly handled conversion of decoded\nREAL values to Python float types. An attacker could possibly use this\nissue to cause applications decoding untrusted ASN.1 data to consume\nexcessive CPU and memory resources, resulting in a denial of service.\n(CVE-2026-59886)",
  "id": "USN-8712-1",
  "modified": "2026-09-01T16:20:26Z",
  "published": "2026-09-01T16:20:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8712-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-59884"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-59885"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-59886"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "pyasn1 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-59884",
    "UBUNTU-CVE-2026-59885",
    "UBUNTU-CVE-2026-59886"
  ]
}



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