UBUNTU-CVE-2026-33846

Source
https://ubuntu.com/security/CVE-2026-33846
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-33846
Upstream
  • CVE-2026-33846
Downstream
Related
Published
2026-05-04T10:15:00Z
Modified
2026-06-02T12:00:06.967548960Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

A heap buffer overflow vulnerability exists in the DTLS handshake fragment reassembly logic of GnuTLS. The issue arises in mergehandshakepacket() where incoming handshake fragments are matched and merged based solely on handshake type, without validating that the messagelength field remains consistent across all fragments of the same logical message. An attacker can exploit this by sending crafted DTLS fragments with conflicting messagelength values, causing the implementation to allocate a buffer based on a smaller initial fragment and subsequently write beyond its bounds using larger, inconsistent fragments. Because the merge operation does not enforce proper bounds checking against the allocated buffer size, this results in an out-of-bounds write on the heap. The vulnerability is remotely exploitable without authentication via the DTLS handshake path and can lead to application crashes or potential memory corruption.

References

Affected packages

Ubuntu:22.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.7.3-4ubuntu1.9

Affected versions

3.*
3.7.1-5ubuntu1
3.7.2-2ubuntu1
3.7.2-4ubuntu1
3.7.2-5ubuntu1
3.7.3-4ubuntu1
3.7.3-4ubuntu1.1
3.7.3-4ubuntu1.2
3.7.3-4ubuntu1.3
3.7.3-4ubuntu1.4
3.7.3-4ubuntu1.5
3.7.3-4ubuntu1.6
3.7.3-4ubuntu1.7
3.7.3-4ubuntu1.8

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.7.3-4ubuntu1.9"
        },
        {
            "binary_name": "guile-gnutls",
            "binary_version": "3.7.3-4ubuntu1.9"
        },
        {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.7.3-4ubuntu1.9"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.7.3-4ubuntu1.9"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.7.3-4ubuntu1.9"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.7.3-4ubuntu1.9"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:24.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.8.3-1.1ubuntu3.6

Affected versions

3.*
3.8.1-4ubuntu1
3.8.1-4ubuntu6
3.8.1-4ubuntu7
3.8.3-1ubuntu1
3.8.3-1.1ubuntu2
3.8.3-1.1ubuntu3
3.8.3-1.1ubuntu3.1
3.8.3-1.1ubuntu3.2
3.8.3-1.1ubuntu3.3
3.8.3-1.1ubuntu3.4
3.8.3-1.1ubuntu3.5

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.8.3-1.1ubuntu3.6"
        },
        {
            "binary_name": "libgnutls-dane0t64",
            "binary_version": "3.8.3-1.1ubuntu3.6"
        },
        {
            "binary_name": "libgnutls-openssl27t64",
            "binary_version": "3.8.3-1.1ubuntu3.6"
        },
        {
            "binary_name": "libgnutls30t64",
            "binary_version": "3.8.3-1.1ubuntu3.6"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:25.10
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.8.9-3ubuntu2.2

Affected versions

3.*
3.8.9-2ubuntu3
3.8.9-3ubuntu1
3.8.9-3ubuntu2
3.8.9-3ubuntu2.1

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.8.9-3ubuntu2.2"
        },
        {
            "binary_name": "libgnutls-dane0t64",
            "binary_version": "3.8.9-3ubuntu2.2"
        },
        {
            "binary_name": "libgnutls-openssl27t64",
            "binary_version": "3.8.9-3ubuntu2.2"
        },
        {
            "binary_name": "libgnutls30t64",
            "binary_version": "3.8.9-3ubuntu2.2"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:26.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.8.12-2ubuntu1.1

Affected versions

3.*
3.8.9-3ubuntu2
3.8.10-3ubuntu1
3.8.12-2ubuntu1

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.8.12-2ubuntu1.1"
        },
        {
            "binary_name": "libgnutls-dane0t64",
            "binary_version": "3.8.12-2ubuntu1.1"
        },
        {
            "binary_name": "libgnutls-openssl27t64",
            "binary_version": "3.8.12-2ubuntu1.1"
        },
        {
            "binary_name": "libgnutls30t64",
            "binary_version": "3.8.12-2ubuntu1.1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:16.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=esm-infra%2Fxenial

Affected ranges

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

Affected versions

3.*
3.3.15-5ubuntu2
3.3.18-1ubuntu1
3.3.20-1ubuntu1
3.4.9-2ubuntu1
3.4.10-4ubuntu1
3.4.10-4ubuntu1.1
3.4.10-4ubuntu1.2
3.4.10-4ubuntu1.3
3.4.10-4ubuntu1.4
3.4.10-4ubuntu1.5
3.4.10-4ubuntu1.6
3.4.10-4ubuntu1.7
3.4.10-4ubuntu1.8
3.4.10-4ubuntu1.9
3.4.10-4ubuntu1.9+esm1
3.4.10-4ubuntu1.9+esm2

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.4.10-4ubuntu1.9+esm2"
        },
        {
            "binary_name": "guile-gnutls",
            "binary_version": "3.4.10-4ubuntu1.9+esm2"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.4.10-4ubuntu1.9+esm2"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.4.10-4ubuntu1.9+esm2"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.4.10-4ubuntu1.9+esm2"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:18.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=esm-infra%2Fbionic

Affected ranges

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

Affected versions

3.*
3.5.8-6ubuntu3
3.5.17-1ubuntu1
3.5.17-1ubuntu3
3.5.18-1ubuntu1
3.5.18-1ubuntu1.1
3.5.18-1ubuntu1.2
3.5.18-1ubuntu1.3
3.5.18-1ubuntu1.4
3.5.18-1ubuntu1.5
3.5.18-1ubuntu1.6
3.5.18-1ubuntu1.6+esm1
3.5.18-1ubuntu1.6+esm2

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.5.18-1ubuntu1.6+esm2"
        },
        {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.5.18-1ubuntu1.6+esm2"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.5.18-1ubuntu1.6+esm2"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.5.18-1ubuntu1.6+esm2"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.5.18-1ubuntu1.6+esm2"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:20.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=esm-infra%2Ffocal

Affected ranges

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

Affected versions

3.*
3.6.9-5ubuntu1
3.6.9-5ubuntu2
3.6.10-5
3.6.11.1-2
3.6.11.1-2ubuntu2
3.6.13-2ubuntu1
3.6.13-2ubuntu1.1
3.6.13-2ubuntu1.2
3.6.13-2ubuntu1.3
3.6.13-2ubuntu1.6
3.6.13-2ubuntu1.7
3.6.13-2ubuntu1.8
3.6.13-2ubuntu1.9
3.6.13-2ubuntu1.10
3.6.13-2ubuntu1.11
3.6.13-2ubuntu1.12
3.6.13-2ubuntu1.12+esm1

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        },
        {
            "binary_name": "guile-gnutls",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        },
        {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.6.13-2ubuntu1.12+esm1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:FIPS-preview:22.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=fips-preview%2Fjammy

Affected ranges

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

Affected versions

3.*
3.7.3-4ubuntu1.2+Fips1.1

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        },
        {
            "binary_name": "guile-gnutls",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        },
        {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.7.3-4ubuntu1.2+Fips1.1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:FIPS-updates:22.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=fips-updates%2Fjammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.7.3-4ubuntu1.9+Fips1

Affected versions

3.*
3.7.3-4ubuntu1.2+Fips1.1
3.7.3-4ubuntu1.3+Fips1.1
3.7.3-4ubuntu1.4+Fips1
3.7.3-4ubuntu1.5+Fips1
3.7.3-4ubuntu1.6+Fips1
3.7.3-4ubuntu1.7+Fips1
3.7.3-4ubuntu1.7+Fips1.1
3.7.3-4ubuntu1.8+Fips1.1

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        },
        {
            "binary_name": "guile-gnutls",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        },
        {
            "binary_name": "libgnutls-dane0",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        },
        {
            "binary_name": "libgnutls-openssl27",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        },
        {
            "binary_name": "libgnutls30",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        },
        {
            "binary_name": "libgnutlsxx28",
            "binary_version": "3.7.3-4ubuntu1.9+Fips1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"
Ubuntu:Pro:FIPS-updates:24.04:LTS
gnutls28

Package

Name
gnutls28
Purl
pkg:deb/ubuntu/gnutls28?arch=source&distro=fips-updates%2Fnoble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.8.3-1.1ubuntu3.6+Fips1.2

Affected versions

3.*
3.8.3-1.1ubuntu3.1+Fips1
3.8.3-1.1ubuntu3.4+Fips1
3.8.3-1.1ubuntu3.4+Fips1.1
3.8.3-1.1ubuntu3.5+Fips1.1

Ecosystem specific

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "gnutls-bin",
            "binary_version": "3.8.3-1.1ubuntu3.6+Fips1.2"
        },
        {
            "binary_name": "libgnutls-dane0t64",
            "binary_version": "3.8.3-1.1ubuntu3.6+Fips1.2"
        },
        {
            "binary_name": "libgnutls-openssl27t64",
            "binary_version": "3.8.3-1.1ubuntu3.6+Fips1.2"
        },
        {
            "binary_name": "libgnutls30t64",
            "binary_version": "3.8.3-1.1ubuntu3.6+Fips1.2"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33846.json"