CVE-2019-20437
When a custom claim dialect with an XSS payload is configured in the identity provider basic claim configuration, that payload gets executed, if a user picks up that dialect's URI as the provisioning claim in the advanced claim configuration of the same…
Does this matter?
Lower severity and a low EPSS score (1.28%). Track it; it rarely justifies an emergency change on its own.
Description
An issue was discovered in WSO2 API Manager 2.6.0, WSO2 IS as Key Manager 5.7.0, and WSO2 Identity Server 5.8.0. When a custom claim dialect with an XSS payload is configured in the identity provider basic claim configuration, that payload gets executed, if a user picks up that dialect's URI as the provisioning claim in the advanced claim configuration of the same Identity Provider. The attacker also needs to have privileges to log in to the management console, and to add and update identity provider configurations.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 1.28% probability · 70th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- wso2/api manager · wso2/identity server
- Source
- cve@mitre.org
EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://cybersecurityworks.com/zerodays/cve-2019-20437-wso2.htmlExploit, Third Party Advisory
- https://docs.wso2.com/display/Security/Security+Advisory+WSO2-2019-0635Vendor Advisory
- https://github.com/cybersecurityworks/Disclosed/issues/20Exploit, Third Party Advisory
- https://cybersecurityworks.com/zerodays/cve-2019-20437-wso2.htmlExploit, Third Party Advisory
- https://docs.wso2.com/display/Security/Security+Advisory+WSO2-2019-0635Vendor Advisory
- https://github.com/cybersecurityworks/Disclosed/issues/20Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.