YiFang CMS P_file.php mergeMultipartUpload unrestricted upload

published 2025-08-25 14 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-25653

cvss: 6.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 27%
public exploits: 0; none known

A flaw has been found in YiFang CMS up to 2.0.5. This affects the function mergeMultipartUpload of the file app/utils/base/plugin/P_file.php. This manipulation of the argument File causes unrestricted upload. Remote exploitation of the attack is possible. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 14 mo ago (2025-08-25)

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/August829/Yu/blob/main/20250811_3.md#poc referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	3.0	6.3	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA	4.0	2.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

YiFang CMS

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type
CWE-284 Improper Access Control

References

github.com /August829/Yu/blob/main/20250811_3.md#poc
exploit, broken-link
vuldb.com /?id.321236
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.321236
signature, permissions-required, vdb-entry
vuldb.com /?submit.632535
third-party-advisory, vdb-entry
github.com /August829/Yu/blob/main/20250811_3.md
related, broken-link

Sources

CVE List CVE-2025-9400
NVD CVE-2025-9400

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary