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Advisory details: vulnrichment / CVE-2026-3872
Advisory ID vulnrichment/CVE-2026-3872
Aliases
Summary A flaw was found in Keycloak. This issue allows an attacker, who controls another path on the same web server, to bypass the allowed path in redirect Uniform Resource Identifiers (URIs) that use a wildcard. A successful attack may lead to the theft of an access token, resulting in information disclosure.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (1)
CWE-601 URL Redirection to Untrusted Site ('Open Redirect')
System Score Found at
cvssv3.1 7.3
ssvc Track
Reference id Reference type URL
https://access.redhat.com/errata/RHSA-2026:6475
https://access.redhat.com/errata/RHSA-2026:6476
cpe:/a:redhat:build_keycloak:26.2::el9 Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:build_keycloak:26.2::el9
cpe:/a:redhat:build_keycloak:26.4::el9 Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:build_keycloak:26.4::el9
CVE-2026-3872 Advisory https://access.redhat.com/security/cve/CVE-2026-3872
RHSA-2026:6477 Advisory https://access.redhat.com/errata/RHSA-2026:6477
RHSA-2026:6478 Advisory https://access.redhat.com/errata/RHSA-2026:6478
show_bug.cgi?id=2445988 Bug https://bugzilla.redhat.com/show_bug.cgi?id=2445988
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N Found at None
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:T/P:M/B:A/M:M/D:T/2026-04-02T13:15:11Z/ Found at None

Vector: SSVCv2/E:N/A:N/T:T/P:M/B:A/M:M/D:T/2026-04-02T13:15:11Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/3xxx/CVE-2026-3872.json

Source Advisory: vulnrichment/CVE-2026-3872

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'no'},
 {'Technical Impact': 'total'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]