USN-8941-1

It was discovered that Squid incorrectly handled certain HTTP Transfer- Encoding headers. An attacker could possibly use this issue to perform HTTP request smuggling attacks, bypass security mechanisms, or poison web caches. (CVE-2026-61642)

It was discovered that Squid incorrectly handled certain cache digest replies, which could lead to a buffer overflow. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-50012)

It was discovered that Squid incorrectly handled parsing certain FTP directory listings. A remote attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-47729)

It was discovered that Squid incorrectly handled certain ICP traffic. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-32748, CVE-2026-33526)

It was discovered that Squid incorrectly handled certain ICP requests. A remote attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-33515)

References

Affected packages

Ubuntu:Pro:16.04:LTS / squid3

Package

Name: squid3
Purl: pkg:deb/ubuntu/squid3?arch=source&distro=esm-infra-legacy%2Fxenial

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

3.5.12-1ubuntu7.16+esm7

Affected versions

3.*

3.3.8-1ubuntu16

3.3.8-1ubuntu17

3.5.12-1ubuntu6

3.5.12-1ubuntu7

3.5.12-1ubuntu7.1

3.5.12-1ubuntu7.2

3.5.12-1ubuntu7.3

3.5.12-1ubuntu7.4

3.5.12-1ubuntu7.5

3.5.12-1ubuntu7.6

3.5.12-1ubuntu7.7

3.5.12-1ubuntu7.8

3.5.12-1ubuntu7.9

3.5.12-1ubuntu7.10

3.5.12-1ubuntu7.11

3.5.12-1ubuntu7.12

3.5.12-1ubuntu7.13

3.5.12-1ubuntu7.14

3.5.12-1ubuntu7.15

3.5.12-1ubuntu7.16

3.5.12-1ubuntu7.16+esm1

3.5.12-1ubuntu7.16+esm2

3.5.12-1ubuntu7.16+esm3

3.5.12-1ubuntu7.16+esm4

3.5.12-1ubuntu7.16+esm5

3.5.12-1ubuntu7.16+esm6

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "squid",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        },
        {
            "binary_name": "squid-cgi",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        },
        {
            "binary_name": "squid-common",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        },
        {
            "binary_name": "squid-purge",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        },
        {
            "binary_name": "squid3",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        },
        {
            "binary_name": "squidclient",
            "binary_version": "3.5.12-1ubuntu7.16+esm7"
        }
    ]
}

Database specific

cves_map

{
    "cves": [
        {
            "id": "CVE-2026-32748",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33515",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33526",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-47729",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-50012",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-61642",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        }
    ],
    "ecosystem": "Ubuntu:Pro:16.04:LTS"
}

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8941-1.json"

Ubuntu:Pro:18.04:LTS / squid3

Package

Name: squid3
Purl: pkg:deb/ubuntu/squid3?arch=source&distro=esm-infra%2Fbionic

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

3.5.27-1ubuntu1.14+esm6

Affected versions

3.*

3.5.23-5ubuntu1

3.5.23-5ubuntu2

3.5.27-1ubuntu1

3.5.27-1ubuntu1.1

3.5.27-1ubuntu1.2

3.5.27-1ubuntu1.3

3.5.27-1ubuntu1.4

3.5.27-1ubuntu1.5

3.5.27-1ubuntu1.6

3.5.27-1ubuntu1.7

3.5.27-1ubuntu1.8

3.5.27-1ubuntu1.9

3.5.27-1ubuntu1.10

3.5.27-1ubuntu1.11

3.5.27-1ubuntu1.12

3.5.27-1ubuntu1.13

3.5.27-1ubuntu1.14

3.5.27-1ubuntu1.14+esm1

3.5.27-1ubuntu1.14+esm2

3.5.27-1ubuntu1.14+esm3

3.5.27-1ubuntu1.14+esm4

3.5.27-1ubuntu1.14+esm5

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "squid",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        },
        {
            "binary_name": "squid-cgi",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        },
        {
            "binary_name": "squid-common",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        },
        {
            "binary_name": "squid-purge",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        },
        {
            "binary_name": "squid3",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        },
        {
            "binary_name": "squidclient",
            "binary_version": "3.5.27-1ubuntu1.14+esm6"
        }
    ]
}

Database specific

cves_map

{
    "cves": [
        {
            "id": "CVE-2026-32748",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33515",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33526",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-47729",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-50012",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-61642",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        }
    ],
    "ecosystem": "Ubuntu:Pro:18.04:LTS"
}

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8941-1.json"

Ubuntu:Pro:20.04:LTS / squid

Package

Name: squid
Purl: pkg:deb/ubuntu/squid?arch=source&distro=esm-infra%2Ffocal

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

4.10-1ubuntu1.13+esm3

Affected versions

4.*

4.8-1ubuntu2

4.8-1ubuntu3

4.9-2ubuntu1

4.9-2ubuntu2

4.9-2ubuntu3

4.9-2ubuntu4

4.10-1ubuntu1

4.10-1ubuntu1.1

4.10-1ubuntu1.2

4.10-1ubuntu1.3

4.10-1ubuntu1.4

4.10-1ubuntu1.5

4.10-1ubuntu1.6

4.10-1ubuntu1.7

4.10-1ubuntu1.8

4.10-1ubuntu1.9

4.10-1ubuntu1.10

4.10-1ubuntu1.11

4.10-1ubuntu1.12

4.10-1ubuntu1.13

4.10-1ubuntu1.13+esm1

4.10-1ubuntu1.13+esm2

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "squid",
            "binary_version": "4.10-1ubuntu1.13+esm3"
        },
        {
            "binary_name": "squid-cgi",
            "binary_version": "4.10-1ubuntu1.13+esm3"
        },
        {
            "binary_name": "squid-common",
            "binary_version": "4.10-1ubuntu1.13+esm3"
        },
        {
            "binary_name": "squid-purge",
            "binary_version": "4.10-1ubuntu1.13+esm3"
        },
        {
            "binary_name": "squidclient",
            "binary_version": "4.10-1ubuntu1.13+esm3"
        }
    ]
}

Database specific

cves_map

{
    "cves": [
        {
            "id": "CVE-2026-32748",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33515",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-33526",
            "severity": [
                {
                    "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H",
                    "type": "CVSS_V4"
                },
                {
                    "score": "CVSS:3.1/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": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-47729",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-50012",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        },
        {
            "id": "CVE-2026-61642",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        }
    ],
    "ecosystem": "Ubuntu:Pro:20.04:LTS"
}

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8941-1.json"

Ubuntu:22.04:LTS / squid

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

5.9-0ubuntu0.22.04.8

Affected versions

4.*

4.13-10ubuntu5

5.*

5.2-1ubuntu1

5.2-1ubuntu3

5.2-1ubuntu4

5.2-1ubuntu4.1

5.2-1ubuntu4.2

5.2-1ubuntu4.3

5.7-0ubuntu0.22.04.1

5.7-0ubuntu0.22.04.2

5.7-0ubuntu0.22.04.3

5.7-0ubuntu0.22.04.4

5.9-0ubuntu0.22.04.1

5.9-0ubuntu0.22.04.2

5.9-0ubuntu0.22.04.3

5.9-0ubuntu0.22.04.4

5.9-0ubuntu0.22.04.5

5.9-0ubuntu0.22.04.7

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "squid",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        },
        {
            "binary_name": "squid-cgi",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        },
        {
            "binary_name": "squid-common",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        },
        {
            "binary_name": "squid-openssl",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        },
        {
            "binary_name": "squid-purge",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        },
        {
            "binary_name": "squidclient",
            "binary_version": "5.9-0ubuntu0.22.04.8"
        }
    ]
}

Database specific

cves_map

{
    "cves": [
        {
            "id": "CVE-2026-61642",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        }
    ],
    "ecosystem": "Ubuntu:22.04:LTS"
}

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8941-1.json"

Ubuntu:24.04:LTS / squid

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

6.14-0ubuntu0.24.04.5

Affected versions

6.*

6.1-2ubuntu1

6.1-2ubuntu2

6.5-1ubuntu1

6.5-1ubuntu2

6.5-1ubuntu3

6.6-1ubuntu4

6.6-1ubuntu5

6.6-1ubuntu5.1

6.10-0ubuntu0.24.04.1

6.13-0ubuntu0.24.04.1

6.13-0ubuntu0.24.04.2

6.13-0ubuntu0.24.04.3

6.14-0ubuntu0.24.04.1

6.14-0ubuntu0.24.04.2

6.14-0ubuntu0.24.04.4

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "squid",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        },
        {
            "binary_name": "squid-cgi",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        },
        {
            "binary_name": "squid-common",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        },
        {
            "binary_name": "squid-openssl",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        },
        {
            "binary_name": "squid-purge",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        },
        {
            "binary_name": "squidclient",
            "binary_version": "6.14-0ubuntu0.24.04.5"
        }
    ]
}

Database specific

cves_map

{
    "cves": [
        {
            "id": "CVE-2026-61642",
            "severity": [
                {
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N",
                    "type": "CVSS_V3"
                },
                {
                    "score": "medium",
                    "type": "Ubuntu"
                }
            ]
        }
    ],
    "ecosystem": "Ubuntu:24.04:LTS"
}

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8941-1.json"