HIGH
CVE-2021-25877
CWE-94Published: November 1, 2021· Updated: Jul 9, 2026
7.2
CVSS v3.1
Official Description
AVideo/YouPHPTube 10.0 and prior is affected by Insecure file write. An administrator privileged user is able to write files on filesystem using flag and code variables in file save.php.
Technical Analysis
CVE-2021-25877 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.2.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.High
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Affected Vendors & Products
youphptube1 product(s)
youphptube
Source: NVD CPE · 1 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (4)
→
https://synacktiv.comProduct
→
https://www.synacktiv.com/sites/default/files/2021-01/YouPHPTube_Multiple_Vulnerabilities.pdfExploit · Vendor Advisory
→
https://synacktiv.comProduct
→
https://www.synacktiv.com/sites/default/files/2021-01/YouPHPTube_Multiple_Vulnerabilities.pdfExploit · Vendor Advisory
Quick Facts
CVE IDCVE-2021-25877
CVSS Score7.2 / 10
SeverityHIGH
WeaknessCWE-94
CISA KEVNo
Affected1 vendor(s)
PublishedNov 1, 2021
Related CVEs (CWE-94)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-25877 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.