TI-2020-17200 Aliases CVE-2020-28361 GHSA-qw54-9qj3-wxh7

Kamailio before 5.4.0, as used in Sip Express Router (SER) in Sippy Softswitch 4.5…

LOW 27CWE-444Published 2020-11-18 · Updated 2024-08-04

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: Low · Low · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Kamailio before 5.4.0, as used in Sip Express Router (SER) in Sippy Softswitch 4.5 through 5.2 and other products, allows a bypass of a header-removal protection mechanism via whitespace characters. This occurs in the remove_hf function in the Kamailio textops module. Particular use of remove_hf in Sippy Softswitch may allow skilled attacker having a valid credential in the system to disrupt internal call start/duration accounting mechanisms leading potentially to a loss of revenue.

Why it matters now

EPSS 0.01108 66th 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
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:kamailio:kamailio::::::::	before 5.4.0	Vulnerable	kamailio

cpe:2.3:a:kamailio:kamailio:*:*:*:*:*:*:*:* Versions before 5.4.0 Vulnerable ·kamailio

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2020-28361
2026-10-03 Alias added: GHSA-qw54-9qj3-wxh7

References

Exploit 1

https://packetstormsecurity.com/files/159030/Kamailio-5.4.0-Header-Smuggling.html

Other 1

https://support.sippysoft.com/support/discussions/topics/3000179616

TI-2020-16681 The Kamailio SIP before 5.5.0 server mishandles INVITE requests with duplicated fields… CVSS 3.1CRITICAL 9.8
TI-2018-06372 A Buffer Overflow issue was discovered in Kamailio before 4.4.7, 5.0.x before 5.0.6, and… CVSS 3.0CRITICAL 9.8
TI-2018-10598 In Kamailio before 5.0.7 and 5.1.x before 5.1.4, a crafted SIP message with a double "To"… CVSS 3.0CRITICAL 9.8
TI-2016-02145 Heap-based buffer overflow in the encode_msg function in encode_msg.c in the SEAS module… CVSS 3.0CRITICAL 9.8
TI-2025-11190 Kamailio Grammar Rule cfg.y yyerror_at null pointer dereference CVSS 4.0MEDIUM 4.8
TI-2025-11189 Kamailio rvalue.c rve_is_constant null pointer dereference CVSS 4.0MEDIUM 4.8

See all 16 →

Sources

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