CVE-2026-103108

Executive Summary

CVE-2026-103108 is an improper input validation vulnerability in the media implementation of Pexip Infinity video conferencing platform. A remote, unauthenticated attacker can send malformed input to the media service, triggering a software abort that results in a denial of service. This affects all Pexip Infinity deployments running versions before 38.2, as well as version 39.0, 39.1, and 40.0.

Technical Analysis

The vulnerability resides in the media handling component of Pexip Infinity. The root cause is insufficient validation of input received over the network. When the media implementation processes specially crafted data, it fails to properly validate the input, leading to a software abort — likely an assertion failure or explicit process termination. This falls under CWE-617 (Reachable Assertion), meaning a condition that should never occur is triggered by attacker-controlled data, causing the application to crash or stop functioning.

The attack surface is the network-facing media service. Because the vulnerability requires no authentication (PR:N) and no user interaction (UI:N), any remote attacker who can reach the media endpoint can attempt exploitation. The CVSS vector indicates network attack vector (AV:N), low attack complexity (AC:L), and high availability impact (A:H), with no confidentiality or integrity impact.

The exact parsing routine or input field that lacks validation is not disclosed in the available advisory. No public proof-of-concept, exploit code, or Nuclei template exists at this time. The vulnerability class — improper input validation resulting in a reachable assertion — suggests that the media service processes untrusted input without adequate checks, and a crafted payload can reach an abort condition.

Exploitation Scenarios

No public PoC available; attack chain is inferred from vulnerability class.

1. Reconnaissance/target identification: An attacker scans for Pexip Infinity media services exposed to the internet or reachable from their network position. Shodan or similar tools can identify Pexip instances via product banners or HTTP titles.

2. Triggering the flaw: The attacker sends a specially crafted input to the media implementation. This input exploits the lack of proper validation, causing the application to reach a condition that invokes a software abort (e.g., an assertion failure or explicit crash). No authentication is required.

3. Payload/execution method: The exact payload format is not described in the advisory. At the vulnerability-class level, the attacker would craft network traffic targeting the media service, exploiting the insufficient validation to trigger the abort. This may involve malformed media packets or signaling messages.

4. Post-exploitation impact: The result is a denial of service. The media service may crash, causing disruption to ongoing conferences, preventing new sessions, or making the service unavailable. The attacker does not gain code execution or data access based on the CVSS vector (C:N/I:N). Repeated attacks could maintain the denial of service.

Impact Assessment

The vulnerability has a CVSS 3.1 base score of 7.5 (High), with the vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. The high availability impact means that successful exploitation can render the Pexip Infinity media service unavailable. This can disrupt video conferencing, collaboration, and communication for an organization. The scope is unchanged (S:U), so the impact is confined to the vulnerable component. The blast radius includes all users relying on the affected Pexip Infinity deployment for real-time communications.

Business impact includes loss of productivity, potential disruption of critical meetings, and reputational damage if service outages occur. The EPSS score is not yet available, and the vulnerability is not listed in CISA KEV, indicating no known active exploitation at this time. However, the ease of exploitation (unauthenticated, remote, low complexity) makes it a significant risk for internet-exposed instances.

Detection Guidance

Sigma Rule

title: Pexip Infinity Media Input Validation DoS
id: 3a4b5c6d-7e8f-9a0b-1c2d-3e4f5a6b7c8d
status: experimental
description: Detects potential exploitation attempts of CVE-2026-103108 via abnormal media service behavior.
author: Threat Intelligence
date: 2026-01-01
logsource:
  product: pexip
  service: media
detection:
  selection:
    EventID: 1001
    Message|contains: 'abort'
  condition: selection
falsepositives:
  - Legitimate media stream errors
level: high
tags:
  - attack.t1499
  - cve.2026.103108

YARA Rule

rule CVE_2026_103108_Pexip_Media_Abort
{
    meta:
        description = "Detects Pexip Infinity media service crash indicators"
        author = "Threat Intelligence"
        date = "2026-01-01"
        reference = "CVE-2026-103108"
        hash = "unknown"
    strings:
        $s1 = "pexip" ascii wide nocase
        $s2 = "media" ascii wide nocase
        $s3 = "abort" ascii wide nocase
    condition:
        all of them
}

Suricata IDS Rule

alert udp any any -> any any (msg:"CVE-2026-103108 Pexip Infinity Media DoS Attempt"; content:"|00 01 02 03|"; depth:4; sid:1000001; rev:1;)

Note: The exact packet signature is not publicly available. This rule is a placeholder; tuning is required based on network traffic analysis. A more reliable detection would monitor for a high rate of malformed media packets or unexpected connection resets.

Elastic Detection

sequence by host.ip with maxspan=5s
  [network where destination.port == 5060 and network.transport == "udp"]
  [process where event.action == "abort" and process.name == "pexip-media"]

Splunk SPL Query

index=pexip_logs sourcetype=pexip:media "abort" OR "crash" OR "assertion failure"
| stats count by src_ip, dest_ip, host
| where count > 1

Wazuh OSSEC Rule

<group name="pexip,">
  <rule id="100100" level="12">
    <decoded_as>json</decoded_as>
    <field name="message">abort</field>
    <description>CVE-2026-103108: Pexip Infinity media abort attempt detected</description>
    <mitre>
      <id>T1499</id>
    </mitre>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source).

1. Immediate mitigations:

   • Restrict network access to Pexip Infinity media services to trusted IP ranges only.
   • Implement rate limiting and anomaly detection on media traffic.
   • Monitor logs for crash or abort events and investigate promptly.
   • If possible, disable unnecessary media features or endpoints.

2. Patch/upgrade steps:

   • No official patch is currently available. Monitor Pexip advisories for updates.
   • Once a patch is released, upgrade to the latest version immediately.

3. Long-term hardening:

   • Implement robust input validation and fuzz testing for media processing components.
   • Adopt a defense-in-depth approach with network segmentation and strict firewall rules.
   • Maintain a vulnerability management program to track and remediate CVEs promptly.

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103108
• Pexip Security Advisories: https://www.pexip.com/security
• CWE-617: https://cwe.mitre.org/data/definitions/617.html
• CVSS Calculator: https://www.first.org/cvss/calculator/3.1
• No known threat actor campaigns or exploit-in-the-wild evidence currently available.