CVE-2018-6520

SimpleSAMLphp before 1.15.2 allows remote attackers to bypass an open redirect protection mechanism via crafted authority data in a URL.

Published: 2018-02-02 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-6520 is rated Low Risk (36.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.17%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-6520

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.25% 0.17% -0.09%
2 2025-03-29 0.15% 0.25% +0.10%
3 2023-03-07 — 0.15% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-6520

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
5.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 4.9 [email protected]

Weakness enumeration for CVE-2018-6520

GitHub Security Advisory for CVE-2018-6520

GHSA-2qfc-48v5-4w5h · Severity: medium · Ecosystem: composer — SimpleSAMLphp Open redirection protection bypass

OS Trackers for CVE-2018-6520

vendor priority summary link
debian not yet assigned CVE-2018-6520 not yet assigned priority: Debian including 1 source packages (simplesamlphp), 3 status rows across 3 suites (bookworm, bullseye, sid): resolved 3. https://security-tracker.debian.org/tracker/CVE-2018-6520
ubuntu medium CVE-2018-6520 medium priority: Ubuntu including 1 source packages (simplesamlphp), 20 status rows across 20 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 16, DNE 1, ignored 1, needed 1, released 1. https://ubuntu.com/security/CVE-2018-6520

Affected software / configurations for CVE-2018-6520

Vendor Product Version Raw CPE
simplesamlphp simplesamlphp >= 1.12.0, < 1.15.1 cpe:2.3:a:simplesamlphp:simplesamlphp:*:*:*:*:*:*:*:*

References for CVE-2018-6520

cvelogic Threat Intelligence