Affected: AlmaLinux:10: coreutils, AlmaLinux:10: coreutils-common, AlmaLinux:10: 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 uniq: Denial of Service and information disclosure via out-of-bounds read with multibyte input (CVE-2026-56391) * 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 uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input.

When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.

This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.

GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input.

When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.

This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.

coreutils-9.11-5.1 on GA media

coreutils: GNU coreutils uniq: Denial of Service and information disclosure via out-of-bounds read with multibyte input

Affected: Rocky Linux:10: coreutils

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 uniq: Denial of Service and information disclosure via out-of-bounds read with multibyte input (CVE-2026-56391)

* 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.

Affected: Ubuntu:26.04:LTS: coreutils

GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input. When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure. This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.