USN-7365-1

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Source
https://ubuntu.com/security/notices/USN-7365-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7365-1.json
JSON Data
https://api.test.osv.dev/v1/vulns/USN-7365-1
Upstream
Related
Published
2025-03-24T01:55:52.738988Z
Modified
2025-10-13T04:40:32Z
Summary
nltk vulnerabilities
Details

It was discovered that NLTK contained a regex that is susceptible to catastrophic backtracking. An attacker could possibly use this issue to cause a denial of service. (CVE-2021-3842, CVE-2021-43854)

References

Affected packages

Ubuntu:Pro:14.04:LTS / nltk

Package

Name
nltk
Purl
pkg:deb/ubuntu/nltk@2.0~b9-0ubuntu4.1~esm4?arch=source&distro=esm-infra-legacy/trusty

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2.0~b9-0ubuntu4.1~esm4

Affected versions

2.*

2.0~b9-0ubuntu4
2.0~b9-0ubuntu4.1~esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "2.0~b9-0ubuntu4.1~esm4",
            "binary_name": "python-nltk"
        }
    ],
    "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:Pro:14.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-3842",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A: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"
                }
            ]
        },
        {
            "id": "CVE-2021-43854",
            "severity": [
                {
                    "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:Pro:16.04:LTS / nltk

Package

Name
nltk
Purl
pkg:deb/ubuntu/nltk@3.1-1ubuntu0.1+esm2?arch=source&distro=esm-apps/xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.1-1ubuntu0.1+esm2

Affected versions

3.*

3.0.4-1
3.0.5-1
3.1-1
3.1-1ubuntu0.1
3.1-1ubuntu0.1+esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "3.1-1ubuntu0.1+esm2",
            "binary_name": "python-nltk"
        },
        {
            "binary_version": "3.1-1ubuntu0.1+esm2",
            "binary_name": "python3-nltk"
        }
    ],
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:Pro:16.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-3842",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A: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"
                }
            ]
        },
        {
            "id": "CVE-2021-43854",
            "severity": [
                {
                    "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:Pro:18.04:LTS / nltk

Package

Name
nltk
Purl
pkg:deb/ubuntu/nltk@3.2.5-1ubuntu0.1+esm2?arch=source&distro=esm-apps/bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.2.5-1ubuntu0.1+esm2

Affected versions

3.*

3.2.4-1
3.2.5-1
3.2.5-1ubuntu0.1
3.2.5-1ubuntu0.1+esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "3.2.5-1ubuntu0.1+esm2",
            "binary_name": "python-nltk"
        },
        {
            "binary_version": "3.2.5-1ubuntu0.1+esm2",
            "binary_name": "python3-nltk"
        }
    ],
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:Pro:18.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-3842",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A: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"
                }
            ]
        },
        {
            "id": "CVE-2021-43854",
            "severity": [
                {
                    "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:Pro:20.04:LTS / nltk

Package

Name
nltk
Purl
pkg:deb/ubuntu/nltk@3.4.5-2ubuntu0.1~esm2?arch=source&distro=esm-apps/focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.4.5-2ubuntu0.1~esm2

Affected versions

3.*

3.4.5-1
3.4.5-2
3.4.5-2ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "3.4.5-2ubuntu0.1~esm2",
            "binary_name": "python3-nltk"
        }
    ],
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:Pro:20.04:LTS",
    "cves": [
        {
            "id": "CVE-2021-3842",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A: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"
                }
            ]
        },
        {
            "id": "CVE-2021-43854",
            "severity": [
                {
                    "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"
                }
            ]
        }
    ]
}