UBUNTU-CVE-2025-31498

Source
https://ubuntu.com/security/CVE-2025-31498
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-31498.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2025-31498
Related
Published
2025-04-08T14:15:00Z
Modified
2025-04-23T15:14:21Z
Summary
[none]
Details

c-ares is an asynchronous resolver library. From 1.32.3 through 1.34.4, there is a use-after-free in readanswers() when processanswer() may re-enqueue a query either due to a DNS Cookie Failure or when the upstream server does not properly support EDNS, or possibly on TCP queries if the remote closed the connection immediately after a response. If there was an issue trying to put that new transaction on the wire, it would close the connection handle, but read_answers() was still expecting the connection handle to be available to possibly dequeue other responses. In theory a remote attacker might be able to trigger this by flooding the target with ICMP UNREACHABLE packets if they also control the upstream nameserver and can return a result with one of those conditions, this has been untested. Otherwise only a local attacker might be able to change system behavior to make send()/write() return a failure condition. This vulnerability is fixed in 1.34.5.

References

Affected packages

Ubuntu:20.04:LTS / c-ares

Package

Name
c-ares
Purl
pkg:deb/ubuntu/c-ares@1.15.0-1ubuntu0.5?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.15.0-1ubuntu0.5

Affected versions

1.*

1.15.0-1build1
1.15.0-1ubuntu0.1
1.15.0-1ubuntu0.2
1.15.0-1ubuntu0.3
1.15.0-1ubuntu0.4

Ecosystem specific

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "binary_version": "1.15.0-1ubuntu0.5",
            "binary_name": "libc-ares-dev"
        },
        {
            "binary_version": "1.15.0-1ubuntu0.5",
            "binary_name": "libc-ares2"
        },
        {
            "binary_version": "1.15.0-1ubuntu0.5",
            "binary_name": "libc-ares2-dbgsym"
        }
    ]
}

Ubuntu:22.04:LTS / c-ares

Package

Name
c-ares
Purl
pkg:deb/ubuntu/c-ares@1.18.1-1ubuntu0.22.04.3?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.18.1-1ubuntu0.22.04.3

Affected versions

1.*

1.17.1-1ubuntu1
1.18.1-1
1.18.1-1build1
1.18.1-1ubuntu0.22.04.1
1.18.1-1ubuntu0.22.04.2

Ecosystem specific

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "binary_version": "1.18.1-1ubuntu0.22.04.3",
            "binary_name": "libc-ares-dev"
        },
        {
            "binary_version": "1.18.1-1ubuntu0.22.04.3",
            "binary_name": "libc-ares2"
        },
        {
            "binary_version": "1.18.1-1ubuntu0.22.04.3",
            "binary_name": "libc-ares2-dbgsym"
        }
    ]
}

Ubuntu:24.10 / c-ares

Package

Name
c-ares
Purl
pkg:deb/ubuntu/c-ares@1.33.0-1?arch=source&distro=oracular

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.27.0-1.0ubuntu1
1.31.0-1
1.32.2-1
1.32.2-2
1.32.3-1
1.33.0-1

Ecosystem specific

{
    "ubuntu_priority": "medium"
}

Ubuntu:24.04:LTS / c-ares

Package

Name
c-ares
Purl
pkg:deb/ubuntu/c-ares@1.27.0-1.0ubuntu1?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.27.0-1.0ubuntu1

Affected versions

1.*

1.19.1-3
1.20.1-1
1.26.0-1
1.27.0-1

Ecosystem specific

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "binary_version": "1.27.0-1.0ubuntu1",
            "binary_name": "libc-ares-dev"
        },
        {
            "binary_version": "1.27.0-1.0ubuntu1",
            "binary_name": "libcares2"
        },
        {
            "binary_version": "1.27.0-1.0ubuntu1",
            "binary_name": "libcares2-dbgsym"
        }
    ]
}

Ubuntu:25.04 / c-ares

Package

Name
c-ares
Purl
pkg:deb/ubuntu/c-ares@1.34.4-2.1?arch=source&distro=plucky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.33.0-1
1.34.2-1
1.34.3-1
1.34.4-1
1.34.4-2.1

Ecosystem specific

{
    "ubuntu_priority": "medium"
}