UBUNTU-CVE-2026-6791

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Source
https://ubuntu.com/security/CVE-2026-6791
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-6791
Upstream
Downstream
Related
Published
2026-08-10T19:17:00Z
Modified
2026-09-10T16:41:40Z
Severity
  • 6.6 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:L/SA:H/E:U CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

When expanding paths that begin with a tilde (~) followed by a username, the internal parse_tilde function extracts the username to determine the user's home directory. The implementation allocates memory for this username directly on the stack using the strndupa macro. Because the size of this allocation was determined by the length of the user-supplied input without any bounds checks, passing an excessively long username e.g. thousands of characters, forces the thread to exhaust its stack space. Thus if an application passes untrusted, attacker-controlled input to the wordexp function, an attacker can trigger a stack clash.

References

Affected packages

Ubuntu:22.04:LTS
glibc

Package

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

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.35-0ubuntu3.15

Affected versions

2.*
2.34-0ubuntu3
2.35-0ubuntu1
2.35-0ubuntu3
2.35-0ubuntu3.1
2.35-0ubuntu3.3
2.35-0ubuntu3.4
2.35-0ubuntu3.5
2.35-0ubuntu3.6
2.35-0ubuntu3.7
2.35-0ubuntu3.8
2.35-0ubuntu3.9
2.35-0ubuntu3.10
2.35-0ubuntu3.11
2.35-0ubuntu3.12
2.35-0ubuntu3.13
2.35-0ubuntu3.14

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc-devtools",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-prof",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-s390",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.35-0ubuntu3.15"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.35-0ubuntu3.15"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:24.04:LTS
glibc

Package

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

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.39-0ubuntu8.9

Affected versions

2.*
2.38-1ubuntu6
2.38-3ubuntu1
2.39-0ubuntu1
2.39-0ubuntu2
2.39-0ubuntu6
2.39-0ubuntu8
2.39-0ubuntu8.1
2.39-0ubuntu8.2
2.39-0ubuntu8.3
2.39-0ubuntu8.4
2.39-0ubuntu8.5
2.39-0ubuntu8.6
2.39-0ubuntu8.7
2.39-0ubuntu8.8

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc-devtools",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-s390",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.39-0ubuntu8.9"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.39-0ubuntu8.9"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:26.04:LTS
glibc

Package

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

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.43-2ubuntu2.4

Affected versions

2.*
2.42-0ubuntu3
2.42-2ubuntu1
2.42-2ubuntu2
2.42-2ubuntu4
2.42-2ubuntu5
2.43-2ubuntu1
2.43-2ubuntu2
2.43-2ubuntu2.3

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc-devtools",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc-gconv-modules-extra",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.43-2ubuntu2.4"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.43-2ubuntu2.4"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:Pro:14.04:LTS
eglibc

Package

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

Affected ranges

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

Affected versions

2.*
2.17-93ubuntu4
2.18-0ubuntu1
2.18-0ubuntu2
2.18-0ubuntu4
2.18-0ubuntu5
2.18-0ubuntu6
2.18-0ubuntu7
2.19-0ubuntu2
2.19-0ubuntu3
2.19-0ubuntu4
2.19-0ubuntu5
2.19-0ubuntu6
2.19-0ubuntu6.1
2.19-0ubuntu6.3
2.19-0ubuntu6.4
2.19-0ubuntu6.5
2.19-0ubuntu6.6
2.19-0ubuntu6.7
2.19-0ubuntu6.8
2.19-0ubuntu6.9
2.19-0ubuntu6.10
2.19-0ubuntu6.11
2.19-0ubuntu6.13
2.19-0ubuntu6.14
2.19-0ubuntu6.15
2.19-0ubuntu6.15+esm1
2.19-0ubuntu6.15+esm2
2.19-0ubuntu6.15+esm3
2.19-0ubuntu6.15+esm4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "eglibc-source",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-armel",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-pic",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-prof",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "multiarch-support",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.19-0ubuntu6.15+esm4"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:Pro:16.04:LTS
glibc

Package

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

Affected ranges

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

Affected versions

2.*
2.21-0ubuntu4
2.21-0ubuntu5
2.21-0ubuntu6
2.23-0ubuntu1
2.23-0ubuntu2
2.23-0ubuntu3
2.23-0ubuntu4
2.23-0ubuntu5
2.23-0ubuntu6
2.23-0ubuntu7
2.23-0ubuntu9
2.23-0ubuntu10
2.23-0ubuntu11
2.23-0ubuntu11.2
2.23-0ubuntu11.3
2.23-0ubuntu11.3+esm1
2.23-0ubuntu11.3+esm2
2.23-0ubuntu11.3+esm3
2.23-0ubuntu11.3+esm5
2.23-0ubuntu11.3+esm6
2.23-0ubuntu11.3+esm7
2.23-0ubuntu11.3+esm8
2.23-0ubuntu11.3+esm9

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-armel",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-pic",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-s390",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "multiarch-support",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.23-0ubuntu11.3+esm9"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:Pro:18.04:LTS
glibc

Package

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

Affected ranges

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

Affected versions

2.*
2.26-0ubuntu2
2.26-0ubuntu2.1
2.27-0ubuntu2
2.27-0ubuntu3
2.27-3ubuntu1
2.27-3ubuntu1.2
2.27-3ubuntu1.3
2.27-3ubuntu1.4
2.27-3ubuntu1.5
2.27-3ubuntu1.6
2.27-3ubuntu1.6+esm1
2.27-3ubuntu1.6+esm2
2.27-3ubuntu1.6+esm3
2.27-3ubuntu1.6+esm4
2.27-3ubuntu1.6+esm5
2.27-3ubuntu1.6+esm6

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-armel",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-lse",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-pic",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-s390",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "multiarch-support",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.27-3ubuntu1.6+esm6"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"
Ubuntu:Pro:20.04:LTS
glibc

Package

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

Affected ranges

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

Affected versions

2.*
2.30-0ubuntu2
2.30-0ubuntu3
2.31-0ubuntu5
2.31-0ubuntu6
2.31-0ubuntu7
2.31-0ubuntu9
2.31-0ubuntu9.1
2.31-0ubuntu9.2
2.31-0ubuntu9.3
2.31-0ubuntu9.7
2.31-0ubuntu9.9
2.31-0ubuntu9.12
2.31-0ubuntu9.14
2.31-0ubuntu9.15
2.31-0ubuntu9.16
2.31-0ubuntu9.17
2.31-0ubuntu9.18
2.31-0ubuntu9.18+esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "glibc-source",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc-bin",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc-dev-bin",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-amd64",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-armel",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-dev-amd64",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-dev-armel",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-dev-i386",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-dev-s390",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-dev-x32",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-i386",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-lse",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-pic",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-prof",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-s390",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "libc6-x32",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "locales",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "locales-all",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        },
        {
            "binary_name": "nscd",
            "binary_version": "2.31-0ubuntu9.18+esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-6791.json"