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TI-2026-28745 Aliases CVE-2026-39864

Kamailio Auth: Processing Vulnerability For Additional Authenticated User Identity Checks

Priority LOW 22CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

Kamailio is an open source implementation of a SIP Signaling Server. Prior to 6.0.5 and 5.8.7, an out-of-bounds read in the auth module of Kamailio (formerly OpenSER and SER) allows remote attackers to cause a denial of service (process crash) via a specially crafted SIP packet if a successful user authentication without a database backend is followed by additional user identity checks. This vulnerability is fixed in 6.0.5 and 5.8.7.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00313 24th percentileScored 2026-11-07
Fix Fixed kamailio (kamailio): 5.8.7, 6.0.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
kamailiokamailiobefore 5.8.7; 6.0.0 to before 6.0.55.8.7, 6.0.5Patch availableCNA
  • kamailio Vendorkamailio Affected before 5.8.7; 6.0.0 to before 6.0.5 Fixed in 5.8.7, 6.0.5 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kamailio:kamailio:*:*:*:*:*:*:*:*before 5.8.7; 6.0.0 to before 6.0.5Vulnerablekamailio
  • cpe:2.3:a:kamailio:kamailio:*:*:*:*:*:*:*:* Versions before 5.8.7; 6.0.0 to before 6.0.5 Vulnerable ·kamailio

Remediation

  • Fix · CNA kamailio (kamailio) Fixed in 5.8.7, 6.0.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-39864

References

Advisory 1

  • 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