CVE-2021-33056

HIGH 7.5CVE-2021-33056 · Published 12/08/2021 · updated 17/06/2026

In short

CVE-2021-33056 is a HIGH (CVSS 7.5) vulnerability affecting belle-sip (linphone).
Chance of exploitation in the next 30 days (EPSS): 1.3%, higher than 70.4% of all vulnerabilities.
Fix: update to 4.5.20 or later.

Package	Affected versions	Patched versions
belle-sip linphone	`< 4.5.20`	`4.5.20`

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.

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