cbcvebase.
CVE-2019-5128
published 2019-10-25

CVE-2019-5128: A command injection have been found in YouPHPTube Encoder. A successful attack could allow an attacker to compromise the server. Exploitable unauthenticated…

PriorityP186critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
30.17%
98.0th percentile
A command injection have been found in YouPHPTube Encoder. A successful attack could allow an attacker to compromise the server. Exploitable unauthenticated command injections exist in YouPHPTube Encoder 2.3 a plugin for providing encoder functionality in YouPHPTube. The parameter base64Url in /objects/getImageMP4.php is vulnerable to a command injection attack.

Affected

2 ranges
VendorProductVersion rangeFixed in
youphptubeyouphptube_encoder
youphptubeyouphptube_encoder

Detection & IOCsextracted from sources · hover to see the quote

path/objects/getImageMP4.php
url/objects/getImageMP4.php?base64Url={{payload}}&format=jpg
  • Detect command injection attempts targeting the `base64Url` parameter in GET requests to `/objects/getImageMP4.php`; the parameter value is a base64-encoded string wrapping a shell command (e.g., backtick-wrapped `id` redirected to a file).
  • The exploit payload is constructed as base64(concat("`", <cmd>, " > ", <filename>, "`")), e.g. base64 of `id > <rand>.txt`. Monitor for base64-encoded strings containing backtick shell metacharacters in the `base64Url` query parameter.
  • Regex match on HTTP response body for `uid=[0-9]+.*gid=[0-9]+.*` to confirm command injection / RCE success on YouPHPTube Encoder endpoints.
  • ·The vulnerability is unauthenticated — no credentials or session tokens are required to exploit the command injection via the `base64Url` parameter.
  • ·The `format` query parameter is also present in the exploit request (`format=jpg`); its role in triggering the vulnerable code path should be accounted for in detection signatures.
  • ·The Nuclei template uses a random 4-character alpha filename for the output file (`{{rand_text_alpha(4)}}.txt`), so the specific filename will vary per exploit attempt; detection should focus on the pattern (short alpha name + `.txt` extension under `/objects/`) rather than a fixed filename.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv3.010.0CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vulncheck9.8CRITICAL
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