Affected: AlmaLinux:9: coreutils, AlmaLinux:9: coreutils-common, AlmaLinux:9: coreutils-single

The coreutils packages contain the GNU Core Utilities and represent a combination of the previously used GNU fileutils, sh-utils, and textutils packages.

Security Fix(es):

* coreutils: GNU coreutils unexpand: Denial of Service via crafted tab stop values (CVE-2026-56392)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

GNU coreutils unexpand is vulnerable to a heap-based buffer overflow due to an integer overflow during buffer allocation when processing large tab stop (-t) values. The multiplication used to calculate the allocation size can wrap around, resulting in an undersized buffer. When processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write.

When running GNU coreutils unexpand with attacker-provided large tab stop (-t) arguments, this behavior leads to a crash and potentially achieve a heap write primitive depending on memory layout.

This issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d

GNU coreutils unexpand is vulnerable to a heap-based buffer overflow due to an integer overflow during buffer allocation when processing large tab stop (-t) values. The multiplication used to calculate the allocation size can wrap around, resulting in an undersized buffer. When processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write.

When running GNU coreutils unexpand with attacker-provided large tab stop (-t) arguments, this behavior leads to a crash and potentially achieve a heap write primitive depending on memory layout.

This issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d

Affected: openEuler:20.03-LTS-SP4: coreutils

These are the GNU core utilities. This package is the combination of the old GNU fileutils, sh-utils, and textutils packages. Security Fix(es):

GNU coreutils unexpand is vulnerable to a heap-based buffer overflow due to an integer overflow during buffer allocation when processing large tab stop (-t) values. The multiplication used to calculate the allocation size can wrap around, resulting in an undersized buffer. When processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write.

When running GNU coreutils unexpand with attacker-provided large tab stop (-t) arguments, this behavior leads to a crash and potentially achieve a heap write primitive depending on memory layout.

This issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d(CVE-2026-56392)

coreutils-9.11-5.1 on GA media

coreutils: GNU coreutils unexpand: Denial of Service via crafted tab stop values

Affected: Rocky Linux:8: coreutils

The coreutils packages contain the GNU Core Utilities and represent a combination of the previously used GNU fileutils, sh-utils, and textutils packages.

Bug Fix(es) and Enhancement(s):

* Fix execution of the downstream tests in coreutils-df-direct.patch and coreutils-i18n.patch [rhel-8.10.z] (JIRA:Rocky Linux-151533)

* unexpand: stack overflow with large tabsizes [rhel-8.10.z] (JIRA:Rocky Linux-182699)

Withdrawn by the publisher.

Affected: Ubuntu:14.04:LTS: coreutils, Ubuntu:16.04:LTS: coreutils, Ubuntu:18.04:LTS: coreutils, Ubuntu:20.04:LTS: coreutils, Ubuntu:22.04:LTS: coreutils, Ubuntu:24.04:LTS: coreutils, Ubuntu:26.04:LTS: coreutils

GNU coreutils unexpand is vulnerable to a heap-based buffer overflow due to an integer overflow during buffer allocation when processing large tab stop (-t) values. The multiplication used to calculate the allocation size can wrap around, resulting in an undersized buffer. When processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write. When running GNU coreutils unexpand with attacker-provided large tab stop (-t) arguments, this behavior leads to a crash and potentially achieve a heap write primitive depending on memory layout. This issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d