UnratedFix available

python-urllib3 vulnerability

Type: advisorySource: OSV1 source record

It was discovered that urllib3 did not correctly strip sensitive HTTP headers during cross-origin redirects. An attacker could possibly use this issue to leak sensitive information.

Announced 24 Sept 2026Source revision 1

Original source ↗

USN-8811-1

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:USN-8811-1

python-urllib3

Source reference: /affected/0/package/name

Affected versions: 1.11-1
Source reference: /affected/0/versions
1.12-1
Source reference: /affected/0/versions
1.13.1-1
Source reference: /affected/0/versions
1.13.1-2
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.1
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.2
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.3
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.4
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.4+esm1
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.4+esm2
Source reference: /affected/0/versions
1.13.1-2ubuntu0.16.04.4+esm3
Source reference: /affected/0/versions
Fixed versions: 1.13.1-2ubuntu0.16.04.4+esm4
Source reference: /affected/0/ranges
Prerequisites: Not stated in this record

python-urllib3

Source reference: /affected/1/package/name

Affected versions: 1.21.1-1
Source reference: /affected/1/versions
1.22-1
Source reference: /affected/1/versions
1.22-1ubuntu0.18.04.1
Source reference: /affected/1/versions
1.22-1ubuntu0.18.04.2
Source reference: /affected/1/versions
1.22-1ubuntu0.18.04.2+esm1
Source reference: /affected/1/versions
1.22-1ubuntu0.18.04.2+esm2
Source reference: /affected/1/versions
1.22-1ubuntu0.18.04.2+esm3
Source reference: /affected/1/versions
Fixed versions: 1.22-1ubuntu0.18.04.2+esm4
Source reference: /affected/1/ranges
Prerequisites: Not stated in this record

python-urllib3

Source reference: /affected/2/package/name

Affected versions: 1.24.1-1ubuntu1
Source reference: /affected/2/versions
1.24.1-1ubuntu2
Source reference: /affected/2/versions
1.25.8-1
Source reference: /affected/2/versions
1.25.8-2
Source reference: /affected/2/versions
1.25.8-2ubuntu0.1
Source reference: /affected/2/versions
1.25.8-2ubuntu0.2
Source reference: /affected/2/versions
1.25.8-2ubuntu0.3
Source reference: /affected/2/versions
1.25.8-2ubuntu0.4
Source reference: /affected/2/versions
1.25.8-2ubuntu0.4+esm1
Source reference: /affected/2/versions
1.25.8-2ubuntu0.4+esm2
Source reference: /affected/2/versions
1.25.8-2ubuntu0.4+esm3
Source reference: /affected/2/versions
1.25.8-2ubuntu0.4+esm4
Source reference: /affected/2/versions
Fixed versions: 1.25.8-2ubuntu0.4+esm5
Source reference: /affected/2/ranges
Prerequisites: Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
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            "fixed": "1.13.1-2ubuntu0.16.04.4+esm4"
          }
        ]
      }
    ],
    "package": {
      "name": "python-urllib3",
      "purl": "pkg:deb/ubuntu/python-urllib3?arch=source&distro=esm-infra-legacy%2Fxenial",
      "ecosystem": "Ubuntu:Pro:16.04:LTS"
    },
    "versions": [
      "1.11-1",
      "1.12-1",
      "1.13.1-1",
      "1.13.1-2",
      "1.13.1-2ubuntu0.16.04.1",
      "1.13.1-2ubuntu0.16.04.2",
      "1.13.1-2ubuntu0.16.04.3",
      "1.13.1-2ubuntu0.16.04.4",
      "1.13.1-2ubuntu0.16.04.4+esm1",
      "1.13.1-2ubuntu0.16.04.4+esm2",
      "1.13.1-2ubuntu0.16.04.4+esm3"
    ],
    "database_specific": {
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      "cves_map": {
        "cves": [
          {
            "id": "CVE-2026-44431",
            "severity": [
              {
                "type": "CVSS_V4",
                "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
              },
              {
                "type": "CVSS_V3",
                "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
              },
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            ]
          }
        ],
        "ecosystem": "Ubuntu:Pro:16.04:LTS"
      }
    },
    "ecosystem_specific": {
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          "binary_name": "python-urllib3",
          "binary_version": "1.13.1-2ubuntu0.16.04.4+esm4"
        },
        {
          "binary_name": "python3-urllib3",
          "binary_version": "1.13.1-2ubuntu0.16.04.4+esm4"
        }
      ],
      "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"
    }
  },
  {
    "ranges": [
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        "events": [
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          }
        ]
      }
    ],
    "package": {
      "name": "python-urllib3",
      "purl": "pkg:deb/ubuntu/python-urllib3?arch=source&distro=esm-infra%2Fbionic",
      "ecosystem": "Ubuntu:Pro:18.04:LTS"
    },
    "versions": [
      "1.21.1-1",
      "1.22-1",
      "1.22-1ubuntu0.18.04.1",
      "1.22-1ubuntu0.18.04.2",
      "1.22-1ubuntu0.18.04.2+esm1",
      "1.22-1ubuntu0.18.04.2+esm2",
      "1.22-1ubuntu0.18.04.2+esm3"
    ],
    "database_specific": {
      "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8811-1.json",
      "cves_map": {
        "cves": [
          {
            "id": "CVE-2026-44431",
            "severity": [
              {
                "type": "CVSS_V4",
                "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
              },
              {
                "type": "CVSS_V3",
                "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
              },
              {
                "type": "Ubuntu",
                "score": "medium"
              }
            ]
          }
        ],
        "ecosystem": "Ubuntu:Pro:18.04:LTS"
      }
    },
    "ecosystem_specific": {
      "binaries": [
        {
          "binary_name": "python-urllib3",
          "binary_version": "1.22-1ubuntu0.18.04.2+esm4"
        },
        {
          "binary_name": "python3-urllib3",
          "binary_version": "1.22-1ubuntu0.18.04.2+esm4"
        }
      ],
      "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
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          },
          {
            "fixed": "1.25.8-2ubuntu0.4+esm5"
          }
        ]
      }
    ],
    "package": {
      "name": "python-urllib3",
      "purl": "pkg:deb/ubuntu/python-urllib3?arch=source&distro=esm-infra%2Ffocal",
      "ecosystem": "Ubuntu:Pro:20.04:LTS"
    },
    "versions": [
      "1.24.1-1ubuntu1",
      "1.24.1-1ubuntu2",
      "1.25.8-1",
      "1.25.8-2",
      "1.25.8-2ubuntu0.1",
      "1.25.8-2ubuntu0.2",
      "1.25.8-2ubuntu0.3",
      "1.25.8-2ubuntu0.4",
      "1.25.8-2ubuntu0.4+esm1",
      "1.25.8-2ubuntu0.4+esm2",
      "1.25.8-2ubuntu0.4+esm3",
      "1.25.8-2ubuntu0.4+esm4"
    ],
    "database_specific": {
      "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8811-1.json",
      "cves_map": {
        "cves": [
          {
            "id": "CVE-2026-44431",
            "severity": [
              {
                "type": "CVSS_V4",
                "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
              },
              {
                "type": "CVSS_V3",
                "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
              },
              {
                "type": "Ubuntu",
                "score": "medium"
              }
            ]
          }
        ],
        "ecosystem": "Ubuntu:Pro:20.04:LTS"
      }
    },
    "ecosystem_specific": {
      "binaries": [
        {
          "binary_name": "python3-urllib3",
          "binary_version": "1.25.8-2ubuntu0.4+esm5"
        }
      ],
      "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event: #13777 · Revision 1
Added to Heist Feed: Sun, 25 Oct 2026 00:30:02 GMT
Publisher date: Thu, 24 Sep 2026 01:39:52 GMT

Read the original announcement