UBUNTU-CVE-2026-19542

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Source
https://ubuntu.com/security/CVE-2026-19542
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-19542.json
JSON Data
https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2026-19542
Upstream
Downstream
Related
Published
2026-08-27T00:00:00Z
Modified
2026-09-16T14:00:42Z
Severity
  • 5.6 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

Calling tdelete on a sufficiently deep tree in the GNU C Library version 2.1 to 2.44 may write one pointer past the end of an alloca-allocated array on the stack, which may crash the application. The tdelete implementation keeps an explicit stack of parent nodes for rebalancing, which is grown as needed while descending the tree. Two rebalancing branches push an additional entry without checking the capacity, and write past the array when the stack is exactly full. Triggering this requires a node at a depth of exactly 40 (or 40 plus a multiple of 20), which implies a tree with at least a million nodes, so an attacker must drive a large number of insertions and deletions through an application that uses tsearch and tdelete. The written value is a pointer into a tree node and is not directly attacker controlled. No affected application in common distributions has been identified.

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-2026-19542.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-2026-19542.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-2026-19542.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-2026-19542.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-2026-19542.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-2026-19542.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-2026-19542.json"