UBUNTU-CVE-2026-6253

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Source

https://ubuntu.com/security/CVE-2026-6253

Import Source

https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json

JSON Data

https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-6253

Upstream

CVE-2026-6253

Downstream

USN-8227-1

Related

USN-8227-1

Published

2026-04-29T14:00:00Z

Modified

2026-05-20T22:03:10.106770050Z

Severity

5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Ubuntu - medium

Summary

[none]

Details

curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say http://), curl is asked to follow a redirect to a URL using another scheme (say https://), accessed using a second, different, proxy

References

Affected packages

Ubuntu:22.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

7.81.0-1ubuntu1.24

Affected versions

7.*

7.74.0-1.3ubuntu2

7.74.0-1.3ubuntu3

7.80.0-3

7.81.0-1

7.81.0-1ubuntu1.1

7.81.0-1ubuntu1.2

7.81.0-1ubuntu1.3

7.81.0-1ubuntu1.4

7.81.0-1ubuntu1.6

7.81.0-1ubuntu1.7

7.81.0-1ubuntu1.8

7.81.0-1ubuntu1.10

7.81.0-1ubuntu1.11

7.81.0-1ubuntu1.13

7.81.0-1ubuntu1.14

7.81.0-1ubuntu1.15

7.81.0-1ubuntu1.16

7.81.0-1ubuntu1.17

7.81.0-1ubuntu1.18

7.81.0-1ubuntu1.19

7.81.0-1ubuntu1.20

7.81.0-1ubuntu1.21

7.81.0-1ubuntu1.22

7.81.0-1ubuntu1.23

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "7.81.0-1ubuntu1.24",
            "binary_name": "curl"
        },
        {
            "binary_version": "7.81.0-1ubuntu1.24",
            "binary_name": "libcurl3-gnutls"
        },
        {
            "binary_version": "7.81.0-1ubuntu1.24",
            "binary_name": "libcurl3-nss"
        },
        {
            "binary_version": "7.81.0-1ubuntu1.24",
            "binary_name": "libcurl4"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:24.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

8.5.0-2ubuntu10.9

Affected versions

8.*

8.2.1-1ubuntu3

8.2.1-1ubuntu3.1

8.4.0-2ubuntu1

8.5.0-2ubuntu1

8.5.0-2ubuntu2

8.5.0-2ubuntu8

8.5.0-2ubuntu9

8.5.0-2ubuntu10

8.5.0-2ubuntu10.1

8.5.0-2ubuntu10.2

8.5.0-2ubuntu10.3

8.5.0-2ubuntu10.4

8.5.0-2ubuntu10.5

8.5.0-2ubuntu10.6

8.5.0-2ubuntu10.7

8.5.0-2ubuntu10.8

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "8.5.0-2ubuntu10.9",
            "binary_name": "curl"
        },
        {
            "binary_version": "8.5.0-2ubuntu10.9",
            "binary_name": "libcurl3t64-gnutls"
        },
        {
            "binary_version": "8.5.0-2ubuntu10.9",
            "binary_name": "libcurl4t64"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:25.10

curl

Package

Name: curl
Purl: pkg:deb/ubuntu/curl?arch=source&distro=questing

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

8.14.1-2ubuntu1.3

Affected versions

8.*

8.12.1-3ubuntu1

8.13.0-5ubuntu1

8.14.1-1ubuntu2

8.14.1-1ubuntu3

8.14.1-2ubuntu1

8.14.1-2ubuntu1.1

8.14.1-2ubuntu1.2

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "8.14.1-2ubuntu1.3",
            "binary_name": "curl"
        },
        {
            "binary_version": "8.14.1-2ubuntu1.3",
            "binary_name": "libcurl3t64-gnutls"
        },
        {
            "binary_version": "8.14.1-2ubuntu1.3",
            "binary_name": "libcurl4t64"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:26.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

8.18.0-1ubuntu2.1

Affected versions

8.*

8.14.1-2ubuntu1

8.17.0-1ubuntu1

8.18.0-1ubuntu1

8.18.0-1ubuntu2

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "8.18.0-1ubuntu2.1",
            "binary_name": "curl"
        },
        {
            "binary_version": "8.18.0-1ubuntu2.1",
            "binary_name": "libcurl3t64-gnutls"
        },
        {
            "binary_version": "8.18.0-1ubuntu2.1",
            "binary_name": "libcurl4t64"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:Pro:14.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

7.*

7.32.0-1ubuntu1

7.33.0-1ubuntu1

7.34.0-1ubuntu1

7.35.0-1ubuntu1

7.35.0-1ubuntu2

7.35.0-1ubuntu2.1

7.35.0-1ubuntu2.2

7.35.0-1ubuntu2.3

7.35.0-1ubuntu2.5

7.35.0-1ubuntu2.6

7.35.0-1ubuntu2.7

7.35.0-1ubuntu2.8

7.35.0-1ubuntu2.9

7.35.0-1ubuntu2.10

7.35.0-1ubuntu2.11

7.35.0-1ubuntu2.12

7.35.0-1ubuntu2.13

7.35.0-1ubuntu2.14

7.35.0-1ubuntu2.15

7.35.0-1ubuntu2.16

7.35.0-1ubuntu2.17

7.35.0-1ubuntu2.19

7.35.0-1ubuntu2.20

7.35.0-1ubuntu2.20+esm2

7.35.0-1ubuntu2.20+esm3

7.35.0-1ubuntu2.20+esm4

7.35.0-1ubuntu2.20+esm5

7.35.0-1ubuntu2.20+esm6

7.35.0-1ubuntu2.20+esm7

7.35.0-1ubuntu2.20+esm8

7.35.0-1ubuntu2.20+esm9

7.35.0-1ubuntu2.20+esm10

7.35.0-1ubuntu2.20+esm11

7.35.0-1ubuntu2.20+esm12

7.35.0-1ubuntu2.20+esm13

7.35.0-1ubuntu2.20+esm14

7.35.0-1ubuntu2.20+esm15

7.35.0-1ubuntu2.20+esm16

7.35.0-1ubuntu2.20+esm17

7.35.0-1ubuntu2.20+esm18

7.35.0-1ubuntu2.20+esm19

Ecosystem specific

{
    "binaries": [
        {
            "binary_version": "7.35.0-1ubuntu2.20+esm19",
            "binary_name": "curl"
        },
        {
            "binary_version": "7.35.0-1ubuntu2.20+esm19",
            "binary_name": "libcurl3"
        },
        {
            "binary_version": "7.35.0-1ubuntu2.20+esm19",
            "binary_name": "libcurl3-gnutls"
        },
        {
            "binary_version": "7.35.0-1ubuntu2.20+esm19",
            "binary_name": "libcurl3-nss"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:Pro:16.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

7.*

7.43.0-1ubuntu2

7.45.0-1ubuntu1

7.46.0-1ubuntu1

7.47.0-1ubuntu1

7.47.0-1ubuntu2

7.47.0-1ubuntu2.1

7.47.0-1ubuntu2.2

7.47.0-1ubuntu2.3

7.47.0-1ubuntu2.4

7.47.0-1ubuntu2.5

7.47.0-1ubuntu2.6

7.47.0-1ubuntu2.7

7.47.0-1ubuntu2.8

7.47.0-1ubuntu2.9

7.47.0-1ubuntu2.11

7.47.0-1ubuntu2.12

7.47.0-1ubuntu2.13

7.47.0-1ubuntu2.14

7.47.0-1ubuntu2.15

7.47.0-1ubuntu2.16

7.47.0-1ubuntu2.18

7.47.0-1ubuntu2.19

7.47.0-1ubuntu2.19+esm1

7.47.0-1ubuntu2.19+esm2

7.47.0-1ubuntu2.19+esm3

7.47.0-1ubuntu2.19+esm4

7.47.0-1ubuntu2.19+esm5

7.47.0-1ubuntu2.19+esm6

7.47.0-1ubuntu2.19+esm7

7.47.0-1ubuntu2.19+esm8

7.47.0-1ubuntu2.19+esm9

7.47.0-1ubuntu2.19+esm10

7.47.0-1ubuntu2.19+esm11

7.47.0-1ubuntu2.19+esm12

7.47.0-1ubuntu2.19+esm13

7.47.0-1ubuntu2.19+esm15

Ecosystem specific

{
    "binaries": [
        {
            "binary_version": "7.47.0-1ubuntu2.19+esm15",
            "binary_name": "curl"
        },
        {
            "binary_version": "7.47.0-1ubuntu2.19+esm15",
            "binary_name": "libcurl3"
        },
        {
            "binary_version": "7.47.0-1ubuntu2.19+esm15",
            "binary_name": "libcurl3-gnutls"
        },
        {
            "binary_version": "7.47.0-1ubuntu2.19+esm15",
            "binary_name": "libcurl3-nss"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:Pro:18.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

7.*

7.55.1-1ubuntu2

7.55.1-1ubuntu2.1

7.57.0-1ubuntu1

7.58.0-2ubuntu1

7.58.0-2ubuntu2

7.58.0-2ubuntu3

7.58.0-2ubuntu3.1

7.58.0-2ubuntu3.2

7.58.0-2ubuntu3.3

7.58.0-2ubuntu3.5

7.58.0-2ubuntu3.6

7.58.0-2ubuntu3.7

7.58.0-2ubuntu3.8

7.58.0-2ubuntu3.9

7.58.0-2ubuntu3.10

7.58.0-2ubuntu3.12

7.58.0-2ubuntu3.13

7.58.0-2ubuntu3.14

7.58.0-2ubuntu3.15

7.58.0-2ubuntu3.16

7.58.0-2ubuntu3.17

7.58.0-2ubuntu3.18

7.58.0-2ubuntu3.19

7.58.0-2ubuntu3.20

7.58.0-2ubuntu3.21

7.58.0-2ubuntu3.22

7.58.0-2ubuntu3.23

7.58.0-2ubuntu3.24

7.58.0-2ubuntu3.24+esm1

7.58.0-2ubuntu3.24+esm2

7.58.0-2ubuntu3.24+esm3

7.58.0-2ubuntu3.24+esm4

7.58.0-2ubuntu3.24+esm5

7.58.0-2ubuntu3.24+esm7

7.58.0-2ubuntu3.24+esm8

Ecosystem specific

{
    "binaries": [
        {
            "binary_version": "7.58.0-2ubuntu3.24+esm8",
            "binary_name": "curl"
        },
        {
            "binary_version": "7.58.0-2ubuntu3.24+esm8",
            "binary_name": "libcurl3-gnutls"
        },
        {
            "binary_version": "7.58.0-2ubuntu3.24+esm8",
            "binary_name": "libcurl3-nss"
        },
        {
            "binary_version": "7.58.0-2ubuntu3.24+esm8",
            "binary_name": "libcurl4"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"

Ubuntu:Pro:20.04:LTS

curl

Package

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

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

7.*

7.65.3-1ubuntu3

7.65.3-1ubuntu4

7.66.0-1ubuntu1

7.67.0-2ubuntu1

7.68.0-1ubuntu1

7.68.0-1ubuntu2

7.68.0-1ubuntu2.1

7.68.0-1ubuntu2.2

7.68.0-1ubuntu2.4

7.68.0-1ubuntu2.5

7.68.0-1ubuntu2.6

7.68.0-1ubuntu2.7

7.68.0-1ubuntu2.10

7.68.0-1ubuntu2.11

7.68.0-1ubuntu2.12

7.68.0-1ubuntu2.13

7.68.0-1ubuntu2.14

7.68.0-1ubuntu2.15

7.68.0-1ubuntu2.16

7.68.0-1ubuntu2.18

7.68.0-1ubuntu2.19

7.68.0-1ubuntu2.20

7.68.0-1ubuntu2.21

7.68.0-1ubuntu2.22

7.68.0-1ubuntu2.23

7.68.0-1ubuntu2.24

7.68.0-1ubuntu2.25

7.68.0-1ubuntu2.25+esm2

7.68.0-1ubuntu2.25+esm3

Ecosystem specific

{
    "binaries": [
        {
            "binary_version": "7.68.0-1ubuntu2.25+esm3",
            "binary_name": "curl"
        },
        {
            "binary_version": "7.68.0-1ubuntu2.25+esm3",
            "binary_name": "libcurl3-gnutls"
        },
        {
            "binary_version": "7.68.0-1ubuntu2.25+esm3",
            "binary_name": "libcurl3-nss"
        },
        {
            "binary_version": "7.68.0-1ubuntu2.25+esm3",
            "binary_name": "libcurl4"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6253.json"