CVE-2026-68768

medium

Description

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.

References

https://www.vulncheck.com/advisories/hashcat-through-heap-buffer-overflow-in-outfile-write-via-oversized-username

https://github.com/hashcat/hashcat/issues/4740

https://github.com/hashcat/hashcat/commit/68f56a2d8712867a8520bf4dcf07f6145c23df89

https://github.com/hashcat/hashcat/blob/v7.1.2/src/outfile.c#L654-L668

https://github.com/hashcat/hashcat

Details

Source: Mitre, NVD

Published: 2026-08-22

Updated: 2026-08-22

Risk Information

CVSS v2

Base Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:C

Severity: Medium

CVSS v3

Base Score: 6.1

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H

Severity: Medium

CVSS v4

Base Score: 6.9

Vector: 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

Severity: Medium

EPSS

EPSS: 0.00186