CVE-2026-68768

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/hashcat/hashcat
https://github.com/hashcat/hashcat/blob/v7.1.2/src/outfile.c#L654-L668
https://github.com/hashcat/hashcat/commit/68f56a2d8712867a8520bf4dcf07f6145c23df89
https://github.com/hashcat/hashcat/issues/4740
https://www.vulncheck.com/advisories/hashcat-through-heap-buffer-overflow-in-outfile-write-via-oversized-username
https://github.com/hashcat/hashcat/issues/4740

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-22 15:16

Updated : 2026-08-24 19:16

NVD link : CVE-2026-68768

Mitre link : CVE-2026-68768

CVE.ORG link : CVE-2026-68768

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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