CVE-2021-21417

Use after free in fluidsynth

Severity Score

5.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

fluidsynth is a software synthesizer based on the SoundFont 2 specifications. A use after free violation was discovered in fluidsynth, that can be triggered when loading an invalid SoundFont file.

fluidsynth es un sintetizador de software basado en las especificaciones de SoundFont 2. Se detectó un uso de la memoria previamente liberada en fluidsynth, que puede ser activado al cargar un archivo SoundFont no válido

*Credits: N/A

CVSS Scores

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-22 CVE Reserved
2021-04-29 CVE Published
2024-08-03 CVE Updated
2024-08-03 First Exploit
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-416: Use After Free

CAPEC

References (4)

URL	Tag	Source
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-6fcq-pxhc-jxc9	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00027.html	Mailing List

URL	Date	SRC
https://github.com/FluidSynth/fluidsynth/issues/808	2024-08-03
https://github.com/FluidSynth/fluidsynth/pull/810	2024-08-03

URL	Date	SRC

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Fluidsynth Search vendor "Fluidsynth"		Fluidsynth Search vendor "Fluidsynth" for product "Fluidsynth"				< 2.1.8 Search vendor "Fluidsynth" for product "Fluidsynth" and version " < 2.1.8"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected