CVE-2026-68768
hashcat through 7.1.2 Heap Buffer Overflow in outfile_write() via Oversized Username
CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-120 |
| Vendor | hashcat |
| Product | hashcat |
| Published | Aug 22, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
High
Affected Versions
hashcat / hashcat
0 ≤ 7.1.2
References
github.com: https://github.com/hashcat/hashcat/issues/4740 github.com: https://github.com/hashcat/hashcat github.com: https://github.com/hashcat/hashcat/commit/68f56a2d8712867a8520bf4dcf07f6145c23df89 github.com: https://github.com/hashcat/hashcat/blob/v7.1.2/src/outfile.c#L654-L668 vulncheck.com: https://www.vulncheck.com/advisories/hashcat-through-heap-buffer-overflow-in-outfile-write-via-oversized-username
Credits
Piotr Kowalczyk