CVE Explorer
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 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 lea
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"defaultStatus":"unaffected","modules":["unexpand"],"product":"coreutils","vendor":"GNU","versions":[{"lessThanOrEqual":"9.11","status":"affected","version":"0","versionType":"custom"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"LOCAL","baseScore":1.8,"baseSeverity":"LOW","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"ACTIVE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"LOW","vulnConfidentialityImpact":…
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/metrics/0/cvssV4_0
CWE assertions
1 source assertion{"cweId":"CWE-122","description":"CWE-122 Heap-based Buffer Overflow","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/problemTypes/0/descriptions/0
Source references
3 source assertions{"tags":["third-party-advisory"],"url":"https://cert.pl/en/posts/2026/07/CVE-2026-56391"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/references/0
{"tags":["product"],"url":"https://git.savannah.gnu.org/cgit/coreutils.git/"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/references/1
{"tags":["patch"],"url":"https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:0c7decc90c0538ebf4b93d6f6c5c0daaa46ea94eef1bd1667f707c382d952189 · sha256:df149d4630c48f39… · /containers/cna/references/2
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.