{"id":"CVE-2026-56391","state":"PUBLISHED","title":"Out‑of‑bounds Read in GNU coreutils","description":"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. \nThis incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input.\n\nWhen running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.\n\n\nThis issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.","publishedAt":"2026-07-24T07:44:45.581Z","updatedAt":"2026-07-24T12:31:34.245Z","severity":{"score":4.6,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N","source":"CERT-PL"},"assigner":"CERT-PL","products":["GNU coreutils"],"affected":[{"vendor":"GNU","product":"coreutils","defaultStatus":"unaffected","versions":[{"version":"9.5","status":"affected","lessThanOrEqual":"9.11","versionType":"custom"}],"modules":["uniq"]}],"references":["https://cert.pl/en/posts/2026/07/CVE-2026-56391","https://git.savannah.gnu.org/cgit/coreutils.git/","https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=d64e35a8a4c0e4608321433e0d84d917e4e36371"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/56xxx/CVE-2026-56391.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-56391","state":"PUBLISHED","datePublished":"2026-07-24T07:44:45.581Z","dateUpdated":"2026-07-24T12:31:34.245Z","assignerShortName":"CERT-PL","assignerOrgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","dateReserved":"2026-06-21T11:40:32.790Z"},"containers":{"cna":{"title":"Out‑of‑bounds Read in GNU coreutils","descriptions":[{"lang":"en","value":"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. \nThis incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input.\n\nWhen running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.\n\n\nThis issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371."}],"affected":[{"vendor":"GNU","product":"coreutils","defaultStatus":"unaffected","versions":[{"version":"9.5","status":"affected","lessThanOrEqual":"9.11","versionType":"custom"}],"modules":["uniq"]}],"references":[{"url":"https://cert.pl/en/posts/2026/07/CVE-2026-56391","tags":["third-party-advisory"]},{"url":"https://git.savannah.gnu.org/cgit/coreutils.git/","tags":["product"]},{"url":"https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=d64e35a8a4c0e4608321433e0d84d917e4e36371","tags":["patch"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"ACTIVE","vulnConfidentialityImpact":"LOW","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":4.6,"vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","lang":"en","description":"CWE-125 Out-of-bounds Read","type":"CWE"}]}],"providerMetadata":{"shortName":"CERT-PL","orgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","dateUpdated":"2026-07-24T07:44:45.581Z"},"tags":["x_open-source"],"credits":[{"lang":"en","value":"Michał Majchrowicz (AFINE Team)","type":"finder"},{"lang":"en","value":"Marcin Wyczechowski (AFINE Team)","type":"finder"}],"source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-24T12:31:16.655541Z","id":"CVE-2026-56391","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-24T12:31:34.245Z"}}]}}}