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Advisory details: vulnrichment / CVE-2026-4874
Advisory ID vulnrichment/CVE-2026-4874
Aliases
Summary A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to 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-918 Server-Side Request Forgery (SSRF)
System Score Found at
cvssv3.1 3.1
ssvc Track
Reference id Reference type URL
https://access.redhat.com/errata/RHSA-2026:30049
https://access.redhat.com/errata/RHSA-2026:30050
cpe:/a:redhat:build_keycloak: Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:build_keycloak:
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
cpe:/a:redhat:build_keycloak:26.6::el9 Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:build_keycloak:26.6::el9
cpe:/a:redhat:jbosseapxp Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:jbosseapxp
cpe:/a:redhat:jboss_enterprise_application_platform:8 Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:jboss_enterprise_application_platform:8
cpe:/a:redhat:red_hat_single_sign_on:7 Other https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:/a:redhat:red_hat_single_sign_on:7
CVE-2026-4874 Advisory https://access.redhat.com/security/cve/CVE-2026-4874
RHSA-2026:25097 Advisory https://access.redhat.com/errata/RHSA-2026:25097
RHSA-2026:25098 Advisory https://access.redhat.com/errata/RHSA-2026:25098
show_bug.cgi?id=2451611 Bug https://bugzilla.redhat.com/show_bug.cgi?id=2451611
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:H/PR:L/UI:N/S:U/C:L/I:N/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:P/P:M/B:A/M:M/D:T/2026-03-26T13:53:59Z/ Found at None

Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-26T13:53:59Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/4xxx/CVE-2026-4874.json

Source Advisory: vulnrichment/CVE-2026-4874

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