cskefu File Upload MediaController.java upload cross site scripting

published 2026-02-16 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-6088

cvss: 3.5; 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 18%
public exploits: 0; none known

A vulnerability was detected in cskefu up to 8.0.1. Impacted is the function Upload of the file com/cskefu/cc/controller/resource/MediaController.java of the component File Upload. The manipulation results in cross site scripting. The attack may be launched remotely. The exploit is now public 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: 8 mo ago (2026-02-17)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

fx4tqqfvdw4.feishu.cn https://fx4tqqfvdw4.feishu.cn/docx/ZqvtdTniToQMw0xZL94cTpuTnac referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
CNA	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	3.0	3.5	CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:UR
CNA	4.0	2.0	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/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	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
NVD	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:P/A:N

Affected products

n/a cskefu

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-94 Improper Control of Generation of Code

References

fx4tqqfvdw4.feishu.cn /docx/ZqvtdTniToQMw0xZL94cTpuTnac
exploit, third-party-advisory
vuldb.com /?id.346165
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.346165
signature, permissions-required, vdb-entry
vuldb.com /?submit.750729
third-party-advisory, vdb-entry

Sources

CVE List CVE-2026-2557
NVD CVE-2026-2557

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