USN-7978-1

It was discovered that GNU Screen incorrectly handled signals when setuid or setgid privileges were being used, which is not the default in Ubuntu. A local attacker could use this issue to send privileged signals, possibly leading to a denial of service. This issue only affected Ubuntu 22.04 LTS. (CVE-2023-24626)

It was discovered that GNU Screen incorrectly handled PTY permissions. A local attacker could possibly use this issue to connect to an unauthorized screen session. (CVE-2025-46802)

It was discovered that GNU Screen incorrectly handled file access when setuid privileges were being used, which is not the default in Ubuntu. A local attacker could use this issue to deduce information about certain file paths. (CVE-2025-46804)

It was discovered that GNU Screen incorrectly handled signals when setuid privileges were being used, which is not the default in Ubuntu. A local attacker could use this issue to send privileged signals, possibly leading to a denial of service. (CVE-2025-46805)

References

Affected packages

Ubuntu:22.04:LTS / screen

Package

Name: screen
Purl: pkg:deb/ubuntu/screen@4.9.0-1ubuntu0.1?arch=source&distro=jammy

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

4.9.0-1ubuntu0.1

Affected versions

4.*

4.8.0-6

4.8.0-6build1

4.8.0-7

4.9.0-1

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "screen",
            "binary_version": "4.9.0-1ubuntu0.1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7978-1.json"

cves_map

{
    "cves": [
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "low"
                }
            ],
            "id": "CVE-2023-24626"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2025-46802"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"
                },
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "low"
                }
            ],
            "id": "CVE-2025-46804"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "low"
                }
            ],
            "id": "CVE-2025-46805"
        }
    ],
    "ecosystem": "Ubuntu:22.04:LTS"
}

Ubuntu:24.04:LTS / screen