---
id: "CVE-2014-3931"
kind: "vulnerability"
aliases: ["CVE-2014-3931"]
title: "multi-router looking glass project multi-router looking glass: fastping.c in MRLG (aka Multi-Router Looking Glass) before 5.5.0 allows remote attackers to cause an arbitrary\u2026"
severity: "critical"
cvss: 9.8
epss: null
exploited: true
status: "open"
category: "other"
products: [{"name": "Looking Glass Multi-Router Looking Glass (MRLG)", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "multi-router looking glass project multi-router looking glass", "fixed": [], "affected": "<= 5.4.1", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "looking-glass", "mrlg", "network-operators", "other"]
not_affected_if: ["not-running-mrlg"]
published_at: "2017-03-31T16:59:00+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T22:29:05+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-3931", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2014-3931", "first_seen_at": "2026-10-23T22:29:05+00:00"}]
---

# multi-router looking glass project multi-router looking glass: fastping.c in MRLG (aka Multi-Router Looking Glass) before 5.5.0 allows remote attackers to cause an arbitrary…

Multi-Router Looking Glass (MRLG) has a buffer overflow that lets remote attackers cause an arbitrary memory write and memory corruption. CISA lists it as known exploited in the wild.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Looking Glass Multi-Router Looking Glass (MRLG) affected ? fixed ?
- vendor:multi-router looking glass project multi-router looking glass affected <= 5.4.1 fixed ?

## Fix

Apply the vendor mitigations per CISA guidance, or discontinue use of MRLG if mitigations are unavailable.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-3931
- 2026-10-23T22:29:05+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2014-3931

## From the sources

Multi-Router Looking Glass (MRLG) contains a buffer overflow vulnerability that could allow remote attackers to cause an arbitrary memory write and memory corruption.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_