TI-2021-04474 Aliases CVE-2021-21375

Crash in receiving updated SDP answer after initial SDP negotiation failed

LOW 33CWE-400Published 2021-03-10 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-400.

Summary

PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In PJSIP version 2.10 and earlier, after an initial INVITE has been sent, when two 183 responses are received, with the first one causing negotiation failure, a crash will occur. This results in a denial of service.

Why it matters now

EPSS 0.0208 81st percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
pjsip	pjproject	up to 2.10	—	No fix listed	CNA

pjproject Vendorpjsip Affected up to 2.10 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:teluu:pjsip::::::::	up to 2.10	Vulnerable	teluu
cpe:2.3:o:debian:debian_linux:9.0:::::::*	9.0	Vulnerable	Debian

cpe:2.3:a:teluu:pjsip:*:*:*:*:*:*:*:* Versions up to 2.10 Vulnerable ·teluu
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Advisory · 2021-03-10
pjsip pjproject — GLSA-202107-42
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2020-12032 Existing TLS connections can be reused without checking remote hostnamePriority LOW 32
Show all 2 records → Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2021-21375

References

Exploit 1

https://github.com/pjsip/pjproject/security/advisories/GHSA-hvq6-f89p-frvp

Patch 1

https://github.com/pjsip/pjproject/commit/97b3d7addbaa720b7ddb0af9bf6f3e443e664365

Advisory 3

TI-2022-13076 Potential stack buffer overflow when parsing message as a STUN client CVSS 3.1CRITICAL 9.8
TI-2022-08599 Potential out-of-bound read/write in PJSIP CVSS 3.1CRITICAL 9.8
TI-2023-20051 PJSIP has use-after-free vulnerability in SRTP media transport CVSS 3.1CRITICAL 9.8
TI-2022-06096 Out-of-bounds read in multipart parsing in PJSIP CVSS 3.1CRITICAL 9.1
TI-2022-07661 Use after free in PJSIP CVSS 3.1CRITICAL 9.8
TI-2022-06095 Potential out-of-bound read during RTP/RTCP parsing in PJSIP CVSS 3.1CRITICAL 9.1

See all 48 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences