Missing custom error page vulnerability in Synology Web Station before 2.1.3-0139 allows remote attackers to conduct phishing attacks via a…

published 2019-04-01 7 y ago modified 2026-06-17 4 mo ago also EUVD-2018-20521

cvss: 7.1; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

Missing custom error page vulnerability in Synology Web Station before 2.1.3-0139 allows remote attackers to conduct phishing attacks via a crafted URL.

Patch / fix

fixed in 1

Synology Web Station 2.1.3-0139

Exploit prediction

1.12% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.1	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
NVD	3.0	6.1	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	5.8	AV:N/AC:M/Au:N/C:P/I:P/A:N

Affected products

Synology Web Station

Classification

Weakness

CWE-756 Missing Custom Error Page
CWE-601 URL Redirection to Untrusted Site

References

synology.com /security/advisory/Synology_SA_18_29
vendor-advisory

Sources

CVE List CVE-2018-8913
NVD CVE-2018-8913

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