USN-7955-1

See a problem?
Please try reporting it to the source first.
Source
https://ubuntu.com/security/notices/USN-7955-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-1.json
JSON Data
https://api.osv.dev/v1/vulns/USN-7955-1
Upstream
Related
Published
2026-01-12T15:31:10Z
Modified
2026-02-10T04:50:47Z
Summary
python-urllib3 vulnerability
Details

It was discovered that urllib3 incorrectly handled decompression during HTTP redirects. An attacker could possibly use this issue to cause urllib3 to use excessive resources, causing a denial of service.

References

Affected packages

Ubuntu:Pro:20.04:LTS / python-urllib3

Package

Name
python-urllib3
Purl
pkg:deb/ubuntu/python-urllib3@1.25.8-2ubuntu0.4+esm3?arch=source&distro=esm-infra/focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.25.8-2ubuntu0.4+esm3

Affected versions

1.*
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

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "1.25.8-2ubuntu0.4+esm3",
            "binary_name": "python3-urllib3"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-1.json"
cves_map 
{
    "ecosystem": "Ubuntu:Pro:20.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-21441",
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:22.04:LTS / python-urllib3

Package

Name
python-urllib3
Purl
pkg:deb/ubuntu/python-urllib3@1.26.5-1~exp1ubuntu0.5?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.26.5-1~exp1ubuntu0.5

Affected versions

1.*
1.26.5-1~exp1
1.26.5-1~exp1ubuntu0.1
1.26.5-1~exp1ubuntu0.2
1.26.5-1~exp1ubuntu0.3
1.26.5-1~exp1ubuntu0.4

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "1.26.5-1~exp1ubuntu0.5",
            "binary_name": "python3-urllib3"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-1.json"
cves_map 
{
    "ecosystem": "Ubuntu:22.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-21441",
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:24.04:LTS / python-urllib3

Package

Name
python-urllib3
Purl
pkg:deb/ubuntu/python-urllib3@2.0.7-1ubuntu0.4?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2.0.7-1ubuntu0.4

Affected versions

1.*
1.26.16-1
1.26.18-1
2.*
2.0.7-1
2.0.7-1ubuntu0.1
2.0.7-1ubuntu0.2
2.0.7-1ubuntu0.3

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2.0.7-1ubuntu0.4",
            "binary_name": "python3-urllib3"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-1.json"
cves_map 
{
    "ecosystem": "Ubuntu:24.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-21441",
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:25.10 / python-urllib3

Package

Name
python-urllib3
Purl
pkg:deb/ubuntu/python-urllib3@2.3.0-3ubuntu0.2?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2.3.0-3ubuntu0.2

Affected versions

2.*
2.3.0-2
2.3.0-2ubuntu1
2.3.0-3
2.3.0-3ubuntu0.1

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2.3.0-3ubuntu0.2",
            "binary_name": "python3-urllib3"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-1.json"
cves_map 
{
    "ecosystem": "Ubuntu:25.10",
    "cves": [
        {
            "id": "CVE-2026-21441",
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}