# DLA-4402-1: libsndfile security update

DLA-4402-1, released December 11, 2025, fixes 1 CVE in libsndfile (version 1.0.31-2+deb11u2). None of them is reported as exploited. Patch Radar priority: High. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/linux/dla-4402-1
- Platform: Linux
- Released: Dec 11, 2025
- Priority: High (Closes CVE-2021-4156, high severity)
- CVEs: 1, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://security-tracker.debian.org/tracker/CVE-2021-4156

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [libsndfile](https://patchblox.com/security/data/product/linux/libsndfile.md) | Debian 11.6 (bullseye) | 1.0.31-2+deb11u2 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-4156](https://patchblox.com/security/data/cve/CVE-2021-4156.md) | High | libsndfile: libsndfile is a C library for reading and writing files containing sampled sound, such as AIFF, AU, or WAV | 8.1 | 0.0175 |  |

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Data as of 2026-11-07T06:34:28Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo