Medium severity · published Sep 14, 2026
CVE-2026-73191
Apache Syncope: CAS service URL injection via Forwarded HTTP headers
6.1
CVSS
0.3%
EPSS
No
On KEV
Description
URL Redirection to Untrusted Site ('Open Redirect') vulnerability in Apache Syncope.
When the Syncope SRA is configured for CAS authentication, the target Apereo CAS instance's URL is calculated by unconditionally looking at client-supplied forwarded HTTP headers.
This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 Through 4.0.7, from 4.1.0-M0 through 4.1.2.
Users are recommended to upgrade to version 4.0.8 / 4.1.3, which fix this issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Apache Syncope · Apache Software Foundation
3.0.0-M0 through 3.0.16; 4.0.0-M0 through 4.0.7; 4.1.0-M0 through 4.1.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73191
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73191
lists.apache.org
https://lists.apache.org/thread/vx9bons1znhdkdpsxwjpy6qqqjc8xqtk
www.openwall.com
http://www.openwall.com/lists/oss-security/2026/09/14/5
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