CVE-2021-33056

—

CVSS 3.1

7.5 high

EPSS

1%p69

Published

Aug 12, 2021 (Aug 12, 2021)

Modified

Jun 17, 2026

Description

Belledonne Belle-sip before 4.5.20, as used in Linphone and other products, can crash via an invalid From header in a SIP message.

Vendors: linphone
Products: belle-sip
Weakness: CWE-444
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD CVE.org GitHub PoCs EPSS (1.3%)

In the news3 stories

Researchers Find Bugs in Over A Dozen Widely Used URL Parser Libraries

The Hacker NewsAug 2, 11:07 UTC · Aug 2, 2022Vulnerability CVE-2021-33056 CVE-2021-23414 CVE-2021-37352+5 CVEs1

60

Critical Remote Hacking Flaws Disclosed in Linphone and MicroSIP Softphones

The Hacker NewsOct 15, 00:00 UTC · Oct 15, 2021Vulnerability CVE-2021-33056

60

Linphone SIP Stack Bug Could Let Attackers Remotely Crash Client Devices

The Hacker NewsSep 2, 11:58 UTC · Sep 2, 2021Vulnerability CVE-2021-33056

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