# CVE-2026-31884

## Summary

- **CVE ID:** CVE-2026-31884
- **Severity:** MEDIUM
- **CVSS Score:** 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H)
- **CWE:** CWE-369
- **Published:** Mar 13, 2026
- **Last Modified:** Mar 16, 2026

## Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, division by zero in MS-ADPCM and IMA-ADPCM decoders when nBlockAlign is 0, leading to a crash. In libfreerdp/codec/dsp.c, both ADPCM decoders use size % block_size where block_size = context->common.format.nBlockAlign. The nBlockAlign value comes from the Server Audio Formats PDU on the RDPSND channel. The value 0 is not validated anywhere before reaching the decoder. When nBlockAlign = 0, the modulo operation causes a SIGFPE (floating point exception) crash. This vulnerability is fixed in 3.24.0.

## Affected Products

- FreeRDP — FreeRDP (< 3.24.0)

## References

- [CNA](https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-jp7m-94ww-p56r)
- [CNA](https://github.com/FreeRDP/FreeRDP/commit/03b48b3601d867afccac1cdc6081de7a275edce7)
- [CNA](https://github.com/FreeRDP/FreeRDP/commit/16df2300e1e3f5a51f68fb1626429e58b531b7c8)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.30%
- **EPSS Percentile:** 22.8

---
_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._