{"id":"UBUNTU-CVE-2026-68768","details":"hashcat contains a heap-based buffer overflow (out-of-bounds write) in the outfile_write() function in src/outfile.c. When assembling output into a fixed-size buffer (HCBUFSIZ_LARGE, ~16 MB), the function sequentially appends the username, separator, hash, and plaintext via memcpy without validating that the accumulated length stays within the buffer capacity. When run with --username --show against a crafted hash file containing an oversized username that nearly fills the buffer, the total assembled output exceeds the buffer, causing a heap buffer overflow that can corrupt memory and crash the process.","modified":"2026-09-02T19:36:28.283673559Z","published":"2026-08-22T15:16:00Z","upstream":["CVE-2026-68768"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-68768"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-68768"},{"type":"REPORT","url":"https://github.com/hashcat/hashcat/issues/4740"},{"type":"REPORT","url":"https://github.com/hashcat/hashcat/pull/4754"}],"affected":[{"package":{"name":"hashcat","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/hashcat?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.60-1","4.0.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.0.1-1","binary_name":"hashcat"},{"binary_version":"4.0.1-1","binary_name":"hashcat-data"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-68768.json"}},{"package":{"name":"hashcat","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/hashcat?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.1.0+ds1-1","5.1.0+ds1-2"],"ecosystem_specific":{"binaries":[{"binary_name":"hashcat","binary_version":"5.1.0+ds1-2"},{"binary_name":"hashcat-data","binary_version":"5.1.0+ds1-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-68768.json"}},{"package":{"name":"hashcat","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/hashcat?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.1.1+ds1-1","6.2.5+ds1-2"],"ecosystem_specific":{"binaries":[{"binary_version":"6.2.5+ds1-2","binary_name":"hashcat"},{"binary_version":"6.2.5+ds1-2","binary_name":"hashcat-data"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-68768.json"}},{"package":{"name":"hashcat","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/hashcat?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.2.6+ds1-1","6.2.6+ds1-1build1","6.2.6+ds1-1build2"],"ecosystem_specific":{"binaries":[{"binary_name":"hashcat","binary_version":"6.2.6+ds1-1build2"},{"binary_version":"6.2.6+ds1-1build2","binary_name":"hashcat-data"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-68768.json"}},{"package":{"name":"hashcat","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/hashcat?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.2.6+ds2-1","7.1.2+ds1-3"],"ecosystem_specific":{"binaries":[{"binary_version":"7.1.2+ds1-3","binary_name":"hashcat"},{"binary_name":"hashcat-data","binary_version":"7.1.2+ds1-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-68768.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}