CVE-2026-68768 (GCVE-0-2026-68768)

Vulnerability from cvelistv5 – Published: 2026-08-22 14:12 – Updated: 2026-08-24 18:31
VLAI
Title
hashcat through 7.1.2 Heap Buffer Overflow in outfile_write() via Oversized Username
Summary
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.
Severity
6.9 (Medium)
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
6.1 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-24 18:31 UTC
CWE
  • CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
References
Impacted products
Vendor Product Version
hashcat hashcat Affected: 0 , ≤ 7.1.2 (semver)
    cpe:2.3:a:hashcat:hashcat:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-31 00:00
Credits
Piotr Kowalczyk
Show details on NVD website
To clipboard 

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