# CVE-2026-54073: VeraCrypt: Hidden volume quick format weakens plausible deniability

CVE-2026-54073 is fixed in VeraCrypt on 1 platform by VeraCrypt 1.26.29 (version 1.26.29), released June 8, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-54073
- Priority: Routine
- CVSS: 4.6
- EPSS: 0.0014
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 21, 2026
- Weakness: CWE-693: Protection Mechanism Failure
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-54073

## Description

VeraCrypt provides disk encryption with strong security based on TrueCrypt. From 1.26.6 until 1.26.29, file-hosted hidden volume creation forces quick format and the FormatNoFs function in src/Common/Format.c and FormatFat function in src/Common/Fat.c use WriteFile to place raw zeroed sectors at predictable 128 MiB intervals. These writes bypass the normal EncryptDataUnits formatting path, leaving deterministic plaintext markers in an area expected to resemble random ciphertext. The markers can weaken plausible deniability during forensic inspection, although they do not disclose hidden-volume content or reduce the strength of VeraCrypt encryption. This issue is fixed in version 1.26.29.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | VeraCrypt | 1.26.29 | [VeraCrypt 1.26.29](https://patchblox.com/security/data/fix/windows-app/idrix.veracrypt-1.26.29.md) | Jun 8, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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