CVE-2026-103102

Executive Summary

CVE-2026-103102 is an improper input validation vulnerability in the signaling component of Pexip Infinity, affecting versions prior to 41.0. A remote, unauthenticated attacker who can reach a gateway call from a WebRTC or API client can supply crafted signaling input that triggers a software abort, resulting in a denial-of-service (DoS) condition against the affected conferencing node. With a CVSS base score of 8.6 (High) and a scope-changed, high-integrity availability impact, this flaw is relevant to any organization exposing Pexip Infinity to untrusted networks or federated WebRTC/API traffic.

Technical Analysis

Pexip Infinity is a distributed software-based video conferencing and collaboration platform that separates its signaling and media functions. The signaling implementation is responsible for negotiating session setup, capabilities, and teardown between clients and gateway/bridge services. CVE-2026-103102 resides in this signaling layer, where input validation is insufficient. According to the NVD description, the flaw is an "improper input validation in the signaling implementation which allows a remote attacker to trigger a software abort resulting in a denial of service."

The vulnerability class maps to CWE-770 (Allocation of Resources Without Limits or Throttling). In practice, this class of weakness describes a situation in which attacker-controlled input is consumed without adequate bounds checking, rate limiting, or resource quotas, causing the process to allocate resources it cannot sustain. In the Pexip context, the observable outcome is not memory corruption or remote code execution but a controlled process termination — a software abort — that halts the affected service. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H confirms the following characteristics: network attack vector, low attack complexity, no privileges required, no user interaction, changed scope, no confidentiality or integrity impact, and high availability impact.

The "changed scope" (S:C) metric is significant because it indicates that exploitation can affect resources beyond the directly vulnerable component. In a distributed conferencing system, a signaling abort on one node may propagate disruption to dependent services or sessions managed by that node.

The precondition for exploitation is a specific one: the attacker must be able to "access a gateway call from a WebRTC/API client." This narrows the attack surface to deployments where WebRTC or API-driven gateway calls are reachable from the attacker's network position. Pexip Infinity deployments frequently expose such interfaces to the public internet to support browser-based and federated conferencing, so the practical exposure is not hypothetical. The signaling protocol implementation itself (session negotiation logic, input parsers, and state handling) is where the missing validation manifests, though the NVD description does not disclose specific function names, message types, or parameters involved.

Because no public proof-of-concept, Nuclei template, or exploit code is available, the exploit chain described below is inferred from the vulnerability class and the stated precondition rather than from a released exploit.

Exploitation Scenarios

The following attack chain is derived strictly from the NVD description and the vulnerability class (CWE-770). No specific function names, API endpoints, or parameters are asserted, because none are provided in the source data. No public PoC is available; the chain below is an inference from the vulnerability class and the stated accessibility condition.

1. Reconnaissance / target identification. The attacker identifies a reachable Pexip Infinity deployment. Targets of interest are those exposing a signaling interface that accepts gateway calls from WebRTC or API clients — typically internet-facing conferencing or API endpoints. Discovery may occur through service fingerprinting, inspection of publicly reachable conferencing portals, or enumeration of hosts responding on conferencing/API ports.

2. Precondition establishment. The attacker must be in a position to reach a gateway call via a WebRTC/API client. This means the attacker either legitimately interacts with the exposed interface or establishes sufficient network reachability to initiate the call path. No authentication is required per the CVSS vector (PR:N), and no user interaction is needed (UI:N).

3. Triggering the flaw class. The attacker initiates a gateway call from a WebRTC/API client and supplies malformed or otherwise unvalidated signaling input. Because the signaling implementation does not adequately validate or throttle the input (CWE-770), the crafted input causes the service to consume resources or enter an invalid state from which it aborts. The precise input that triggers the abort is not documented in the available data; the attack is characterized at the class level as "crafted signaling input triggering an uncontrolled resource/abort condition."

4. Post-exploitation impact. The result is a software abort — a process or service termination — producing a denial-of-service condition. The CVSS subscores indicate only availability is impacted (A:H), with no confidentiality (C:N) or integrity (I:N) impact. The changed scope (S:C) suggests the disruption may extend beyond the initially affected component. Repeated triggering could sustain the DoS, denying conferencing service to legitimate users, though the description does not confirm whether the aborted component restarts automatically.

Impact Assessment

The CVSS v3.1 base score of 8.6 (High) is driven by a favorable attack profile: network reachable (AV:N), low complexity (AC:L), no privileges (PR:N), and no user interaction (UI:N), combined with a high availability impact (A:H) and changed scope (S:C). There are no confidentiality or integrity impacts.

Business impact centers on service availability. Pexip Infinity is used for enterprise video conferencing, gateway connectivity to legacy systems, and federated meetings. A denial-of-service condition in the signaling path can disrupt scheduled and ad hoc conferences, break gateway calls, and impair API-driven integrations. Because the changed scope metric is set, the blast radius may include dependent sessions or services beyond the vulnerable node. Organizations without redundant conferencing infrastructure or failover may experience a full outage of the affected service for the duration of the attack.

The absence of a CISA KEV listing and the lack of a public PoC or exploit code lower the immediate likelihood of opportunistic mass exploitation. However, the low attack complexity and unauthenticated nature of the flaw make it attractive for targeted disruption, hacktivist activity, or denial-of-service campaigns once technical details become public. No affected version list or OSV package data is available, so the exact version inventory must be confirmed against vendor documentation.

Detection Guidance

Detection should focus on abnormalities in the signaling path: unexpected aborts or service restarts, malformed signaling traffic from WebRTC/API clients, and spikes in failed gateway call attempts. Because no specific payload is documented, detections are behavioral and signature-based at the vulnerability-class level. All rules below are illustrative and should be tuned to the local environment.

Sigma Rule

title: Pexip Infinity Signaling Abort Potential DoS (CVE-2026-103102)
id: 6f2c1b8e-3d4a-4c9e-9b1f-0a7e5d2c9f11
status: experimental
description: Detects process abort or abnormal termination of Pexip Infinity signaling services, which may indicate exploitation of CVE-2026-103102 via crafted WebRTC/API signaling input.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-103102
author: valtersit.com
date: 2026/01/01
logsource:
  category: process_termination
  product: linux
detection:
  selection_name:
    Image|endswith:
      - '/pexip'
      - '/infinity'
  selection_abort:
    ExitCode|in:
      - 134   # SIGABRT
      - 139   # SIGSEGV
  condition: selection_name and selection_abort
falsepositives:
  - Planned service restarts
  - Upgrades and maintenance windows
level: high
tags:
  - attack.t1190
  - cve.2026.103102

YARA Rule

rule CVE_2026_103102_Pexip_Signaling_Abort_Indicator
{
    meta:
        description = "Heuristic indicator for processes associated with Pexip Infinity signaling; supports investigation of CVE-2026-103102 aborts"
        author = "valtersit.com"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-103102"
        date = "2026-01-01"
        cve = "CVE-2026-103102"

    strings:
        $p1 = "Pexip Infinity" ascii wide nocase
        $p2 = "WebRTC" ascii wide
        $p3 = "gateway call" ascii wide nocase
        $sig_abort = { FF ?? } // placeholder for signal/abort context

    condition:
        uint16(0) == 0x5A4D or uint32(0) == 0x464C457F
        and any of ($p1, $p2, $p3)
}

Note: YARA is not a primary detection layer for this network-input-driven aborts; the above is a heuristic for artifact triage only.

Suricata IDS Rule

alert tcp any any -> any any (msg:"CVE-2026-103102 Pexip Infinity signaling abort DoS attempt (WebRTC/API gateway call)"; flow:established,to_server; content:"|00 00|"; depth:2; threshold: type both, track by_src, count 20, seconds 60; classtype:attempted-dos; reference:cve,2026-103102; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-103102; sid:2026103102; rev:1;)

Placeholder pattern only — replace the content match with the environment-specific signaling protocol signature once vendor protocol details are available. The rule is provided to satisfy structural guidance for reporting; it is not a validated signature.

Elastic Detection

process where event.type == "end" and process.name like~ ("pexip", "infinity") and process.exit_code in (134, 139)

This EQL rule detects abnormal termination (SIGABRT/SIGSEGV) of Pexip Infinity-related processes, consistent with a signaling abort.

Splunk SPL Query

index=* (sourcetype=syslog OR source="*pexip*")
| search ("Pexip" OR "infinity" OR "signaling")
| search ("abort" OR "SIGABRT" OR "core dumped" OR "terminated")
| stats count by host, process, _time
| where count > 0

Tune the index and sourcetype to the local Pexip log ingestion pipeline. The query surfaces abort/core-dump indicators in signaling services.

Wazuh OSSEC Rule

<group name="pexip,cve-2026-103102,">
  <rule id="103102" level="12">
    <decoded_as>syslog</decoded_as>
    <match>Pexip|infinity</match>
    <regex>abort|SIGABRT|core dumped|terminated</regex>
    <description>CVE-2026-103102: Possible Pexip Infinity signaling abort / DoS condition detected</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>denial_of_service,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). The NVD description states the flaw affects "Pexip Infinity before 41.0," which implies remediation by upgrading to 41.0 or later, but no vendor advisory or verified fix artifact is present in the tracked sources.

1. Immediate mitigations.

   • Restrict network access to Pexip Infinity signaling interfaces that accept WebRTC/API gateway calls. Apply firewall rules and allowlisting so only trusted client networks, federated partners, and required API consumers can reach the signaling path.
   • Rate-limit and monitor inbound signaling connections. Because the flaw maps to CWE-770 (Allocation of Resources Without Limits or Throttling), front-end rate limiting and connection quotas can reduce the ability to trigger resource exhaustion.
   • Deploy the detection rules above and alert on abnormal signaling-service termination or restart events.
   • Consider redundant conferencing nodes or failover so that an abort on one node does not cause a full outage.

2. Patch/upgrade steps.

   • Consult the vendor (Pexip) for the official security advisory and fixed release. The NVD description indicates versions before 41.0 are affected; upgrading to 41.0 or later is the presumed remediation path.
   • Validate the exact fixed build against vendor release notes before deployment. Do not treat this report as confirmation of a patch, since patch confidence is 0/4.
   • Stage upgrades in a test environment, verify signaling functionality, then roll out to production.

3. Long-term hardening.

   • Enforce strict input validation and schema enforcement at any reverse proxy or session border controller in front of Pexip signaling services where feasible.
   • Segment conferencing infrastructure from general corporate networks and limit east-west movement.
   • Maintain continuous monitoring for service aborts and maintain an inventory of internet-facing conferencing endpoints.
   • Subscribe to vendor security bulletins and monitor NVD for updated CVE-2026-103102 metadata, including any affected-version list or proof-of-concept.

References

• NVD — CVE-2026-103102: https://nvd.nist.gov/vuln/detail/CVE-2026-103102
• MITRE CWE-770 — Allocation of Resources Without Limits or Throttling: https://cwe.mitre.org/data/definitions/770.html
• MITRE ATT&CK T1190 — Exploit Public-Facing Application: https://attack.mitre.org/techniques/T1190/
• FIRST EPSS (not yet scored for this CVE at time of writing): https://www.first.org/epss/
• CISA Known Exploited Vulnerabilities Catalog (CVE-2026-103102 not listed at time of writing): https://www.cisa.gov/known-exploited-vulnerabilities-catalog

No threat actor campaigns or exploit-in-the-wild evidence were identified in the provided data. No public proof-of-concept, Nuclei template, or exploit code is available as of this report.