UBUNTU-CVE-2026-86000

Source
https://ubuntu.com/security/CVE-2026-86000
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86000.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-86000
Upstream
Published
2026-09-21T00:00:00Z
Modified
2026-09-21T21:41:00Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.9, the selector parser in src/soupsieve/css_parser.py defines IDENTIFIER with adjacent quantified groups over overlapping character classes, and VALUE embeds IDENTIFIER for attribute selectors. When an attacker-controlled selector contains a long identifier or unquoted attribute-value run followed by input that makes the overall match fail, the regular expression engine explores quadratically many splits between the overlapping groups. User-controlled selectors can reach this path through soupsieve.compile(), soupsieve.select(), or BeautifulSoup.select(), while applications using only hard-coded selectors are unaffected. The resulting CPU consumption can hold the Python GIL, exhaust application workers, and stall a service; successful plain identifier matches are linear, and the issue does not cause memory corruption or code execution. The issue is fixed in version 2.9.

References

Affected packages

Ubuntu:20.04:LTS / soupsieve

Package

Name
soupsieve
Purl
pkg:deb/ubuntu/soupsieve?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.9.2+dfsg-2ubuntu1
1.9.4+dfsg-1
1.9.5+dfsg-1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "python-soupsieve",
            "binary_version":  "1.9.5+dfsg-1"
        },
        {
            "binary_name":  "python3-soupsieve",
            "binary_version":  "1.9.5+dfsg-1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86000.json"

Ubuntu:22.04:LTS / soupsieve

Package

Name
soupsieve
Purl
pkg:deb/ubuntu/soupsieve?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.2.1-2
2.3-1
2.3.1-1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "python3-soupsieve",
            "binary_version":  "2.3.1-1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86000.json"

Ubuntu:24.04:LTS / soupsieve

Package

Name
soupsieve
Purl
pkg:deb/ubuntu/soupsieve?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.4.1-2
2.5-1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "python3-soupsieve",
            "binary_version":  "2.5-1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86000.json"

Ubuntu:26.04:LTS / soupsieve

Package

Name
soupsieve
Purl
pkg:deb/ubuntu/soupsieve?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.7-2
2.8.1-1
2.8.3-1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "python3-soupsieve",
            "binary_version":  "2.8.3-1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86000.json"