# CVE-2026-68768: hashcat heap-based buffer overflow in outfile_write

Source: https://junglewise.ai/threats/cve-2026-68768-hashcat-heap-based-buffer-overflow-in-outfile-write  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-22. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-68768 · Severity: medium · CVSS 6.1 · Published 2026-08-22

hashcat is a password recovery and cracking tool widely used by security professionals and attackers. When processing specially crafted hash files with the --username and --show options, the tool fails to validate that assembled output fits within its internal buffer, leading to a heap overflow that can crash the application or potentially corrupt memory.

Technologies: [Hashcat](https://junglewise.ai/threats/technologies/hashcat). Vendors: [Hashcat](https://junglewise.ai/threats/vendors/hashcat).

## Quick answers

**Is CVE-2026-68768 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-68768 being exploited in the wild.

**How severe is CVE-2026-68768?** Medium severity, with a CVSS score of 6.1, published 22 August 2026.

**Which products and versions are affected?** Hashcat prior to v7.2.0.

**Is there a fix for CVE-2026-68768?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-68768 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-68768?** Check whether you run Hashcat at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a heap-based buffer overflow (out-of-bounds write) in the outfile_write() function in src/outfile.c. The function sequentially appends username, separator, hash, and plaintext to a fixed-size buffer (HCBUFSIZ_LARGE, approximately 16 MB) using memcpy without validating the accumulated length against buffer capacity. When run with --username --show against a crafted hash file containing an oversized username, the total assembled output exceeds the buffer boundary, causing heap corruption. Attack vector is local; requires the attacker to supply a malicious hash file to the hashcat process.

## Affected products

- hashcat hashcat prior to v7.2.0

## Timeline

- 2026-08-22: disclosed

## References

- [https://github.com/hashcat/hashcat](https://github.com/hashcat/hashcat)
- [https://github.com/hashcat/hashcat/blob/v7.1.2/src/outfile.c](https://github.com/hashcat/hashcat/blob/v7.1.2/src/outfile.c)

## Related threats

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