CVE catalog
CVE-2026-56392
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 calculat
- Severity
- Medium · CVSS 4.4
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.19% · Oct 25, 2026
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
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | coreutils | sid | 9.10-1 | vulnerable |
| Debian | coreutils | forky | 9.10-1 | vulnerable |
| Debian | coreutils | trixie | 9.7-3 | vulnerable |
| Debian | coreutils | bookworm | 9.1-1 | vulnerable |
| Cpe | coreutils | Not reported | Not reported | unknown |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | coreutils | source | sid | (unfixed) | unimportant | Not reported | Not reported |
| Debian | coreutils | source | forky | (unfixed) | unimportant | Not reported | Not reported |
| Debian | coreutils | source | trixie | (unfixed) | unimportant | Not reported | Not reported |
| Debian | coreutils | source | bookworm | (unfixed) | unimportant | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [coreutils]Affected
Details (2)
9.1-1· amd64 · bookwormAffected
nvd · coreutils · debian · bookworm; nvd · coreutils · debian · 12
9.1-1· arm64 · bookwormAffected
nvd · coreutils · debian · bookworm; nvd · coreutils · debian · 12
[Debian 13 (Trixie)]
- [coreutils]Affected
Details (2)
9.7-3· amd64 · trixieAffected
nvd · coreutils · debian · 13
9.7-3· arm64 · trixieAffected
nvd · coreutils · debian · 13
Observed:
References
- [https://cert.pl/en/posts/2026/07/CVE-2026-56391]
- [https://ftp.suse.com/pub/projects/security/csaf/rhba-2026_47115.json]
- [https://git.savannah.gnu.org/cgit/coreutils.git/]
- [https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-56392]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-56392]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-56392]
- [https://security-tracker.debian.org/tracker/CVE-2026-56392]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56392.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-3319.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]