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Vulnerability · Published Aug 22, 2026 · Assigned by VulnCheck

CVE-2026-68768hashcat through 7.1.2 Heap Buffer Overflow in outfile_write() via Oversized Username

Medium 6.1

In plain English

A medium-severity buffer overflow in hashcat from hashcat. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).

Severity (CVSS 3.1)6.1Medium
Exploit odds (30 days)0.2%top 88.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12hashcatno fix listedDEBIAN-CVE-2026-68768
Debian:13hashcatno fix listedDEBIAN-CVE-2026-68768
Debian:14hashcatno fix listedDEBIAN-CVE-2026-68768
Ubuntu:22.04:LTShashcatno fix listedUBUNTU-CVE-2026-68768
Ubuntu:24.04:LTShashcatno fix listedUBUNTU-CVE-2026-68768
Ubuntu:26.04:LTShashcatno fix listedUBUNTU-CVE-2026-68768
Ubuntu:26.10hashcatno fix listedUBUNTU-CVE-2026-68768

Affected products (as reported)

VendorProductVersions
hashcat hashcat 0 – through 7.1.2

Weakness: CWE-120 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H

References