High severity · published Aug 29, 2022
CVE-2020-26938
In oauth2-server (aka node-oauth2-server) through 3.1.1, the value of the redirect_uri parameter received during the authorization and token request is checked against an…
7.2
CVSS
1%
EPSS
No
On KEV
Description
In oauth2-server (aka node-oauth2-server) through 3.1.1, the value of the redirect_uri parameter received during the authorization and token request is checked against an incorrect URI pattern ("[a-zA-Z][a-zA-Z0-9+.-]+:") before making a redirection. This allows a malicious client to pass an XSS payload through the redirect_uri parameter while making an authorization request. NOTE: this vulnerability is similar to CVE-2020-7741.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 62% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OA
Oauth2-server · Oauth2-server Project
through 3.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26938
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-26938
Exploit
https://github.com/oauthjs/node-oauth2-server/blob/91d2cbe70a0eddc53d72def96864e2de0fd41703/lib/grant-types/authorization-code-grant-type.js#L143
Exploit
https://github.com/oauthjs/node-oauth2-server/blob/91d2cbe70a0eddc53d72def96864e2de0fd41703/lib/validator/is.js#L12
Issue Tracking
https://github.com/oauthjs/node-oauth2-server/issues/637
Third Party Advisory
https://tools.ietf.org/html/rfc3986#section-3
Third Party Advisory
https://tools.ietf.org/html/rfc6749#section-3.1.2
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