USN-4896-1

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Source
https://ubuntu.com/security/notices/USN-4896-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4896-1.json
JSON Data
https://api.osv.dev/v1/vulns/USN-4896-1
Upstream
Related
Published
2021-03-30T16:24:59.616623Z
Modified
2025-12-19T20:26:38.963004Z
Summary
lxml vulnerability
Details

It was discovered that lxml incorrectly handled certain HTML attributes. A remote attacker could possibly use this issue to perform cross-site scripting (XSS) attacks.

References

Affected packages

Ubuntu:16.04:LTS / lxml

Package

Name
lxml
Purl
pkg:deb/ubuntu/lxml@3.5.0-1ubuntu0.4?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.5.0-1ubuntu0.4

Affected versions

3.*

3.4.4-1
3.5.0-1
3.5.0-1build1
3.5.0-1ubuntu0.1
3.5.0-1ubuntu0.2
3.5.0-1ubuntu0.3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python-lxml",
            "binary_version": "3.5.0-1ubuntu0.4"
        },
        {
            "binary_name": "python3-lxml",
            "binary_version": "3.5.0-1ubuntu0.4"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4896-1.json"

cves_map

{
    "ecosystem": "Ubuntu:16.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-28957",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:18.04:LTS / lxml

Package

Name
lxml
Purl
pkg:deb/ubuntu/lxml@4.2.1-1ubuntu0.4?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.2.1-1ubuntu0.4

Affected versions

4.*

4.0.0-1
4.1.0-1
4.2.0-1
4.2.1-1
4.2.1-1ubuntu0.1
4.2.1-1ubuntu0.2
4.2.1-1ubuntu0.3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python-lxml",
            "binary_version": "4.2.1-1ubuntu0.4"
        },
        {
            "binary_name": "python3-lxml",
            "binary_version": "4.2.1-1ubuntu0.4"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4896-1.json"

cves_map

{
    "ecosystem": "Ubuntu:18.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-28957",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:20.04:LTS / lxml

Package

Name
lxml
Purl
pkg:deb/ubuntu/lxml@4.5.0-1ubuntu0.3?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.5.0-1ubuntu0.3

Affected versions

4.*

4.4.1-1
4.4.1-1build1
4.4.2-1
4.5.0-1
4.5.0-1ubuntu0.1
4.5.0-1ubuntu0.2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python-lxml",
            "binary_version": "4.5.0-1ubuntu0.3"
        },
        {
            "binary_name": "python3-lxml",
            "binary_version": "4.5.0-1ubuntu0.3"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4896-1.json"

cves_map

{
    "ecosystem": "Ubuntu:20.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-28957",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}