CVE-2026-39863

Kamailio Core: TCP Data Processing Vulnerability

HIGH
7.5
CVSS Score
Published: April 8, 2026 at 07:55 PM UTC
Updated: July 24, 2026 at 09:20 PM UTC
1 product affected across 1 vendorKamailio

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Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Kamailio is an open source implementation of a SIP Signaling Server. Prior to 6.1.1, 6.0.6, and 5.8.8, an out-of-bounds access in the core of Kamailio (formerly OpenSER and SER) allows remote attackers to cause a denial of service (process crash) via a specially crafted data packet sent over TCP. The issue impacts Kamailio instances having TCP or TLS listeners. This vulnerability is fixed in 5.1.1, 6.0.6, and 5.8.8.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 5.8.8v < 6.0.6v < 6.1.16.0.0 ≤ v < 6.0.66.1.0
Affected range stops below 5.8.8, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.0.6, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.1.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMVendor Advisory
Source: cverecord
https://github.com/kamailio/kamailio/security/advisories/GHSA-2wj4-f825-2h2f

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-119

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