SIPSorcery: Malformed UDP packet on the RTP/ICE socket can remotely terminate a media session (DoS)

published 2026-07-28 3 mo ago modified 2026-09-30 39 d ago also GHSA-28gm-jrmw-xx93 , EUVD-2026-78055

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

SIPSorcery is a WebRTC, SIP, and VoIP library for C# and .NET. Prior to 10.0.9, RTPChannel.OnRTPPacketReceived and the STUNAttribute.ParseMessageAttributes, STUNXORAddressAttribute, and STUNAddressAttribute parsing path index untrusted bytes without sufficient length checks, while UdpReceiver.EndReceiveFrom closes the channel when those operations raise a non-socket exception. A remote party can send a single short RTP packet or malformed zero-to-seven-byte STUN address attribute to the shared RTP/ICE socket, including during ICE connectivity checks before DTLS or STUN MESSAGE-INTEGRITY verification, and terminate the active RTP or WebRTC media session. The attacker must reach or learn the advertised ephemeral RTP/ICE port, but no authentication or user interaction is required, and the impact is limited to availability. This issue is fixed in version 10.0.9.

Patch / fix

fixed in 1 links 2

nuget SIPSorcery 10.0.9

github.com/sipsorcery-org/sipsorcery@bdb76cb commit
github.com/sipsorcery-org/sipsorcery#1677 pull request

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 55 d ago (2026-09-15)

Exploit prediction

0.72% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
nuget	SIPSorcery	<10.0.9	10.0.9

Affected products

sipsorcery-org sipsorcery

Classification

Weakness

CWE-20 Improper Input Validation
CWE-755 Improper Handling of Exceptional Conditions

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary