From e44df496cec4f5b5420134a8621e9266859e2536 Mon Sep 17 00:00:00 2001
From: jimmychakkalakal <47317106+jimmychakkalakal@users.noreply.github.com>
Date: Thu, 18 Jun 2026 15:04:12 +0000
Subject: [PATCH] Reject redirect URIs containing pre-loaded OIDC response parameters (#49959)
---
src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java | 273 ++++++++++++++++++++++++++++++++++++++----------------
1 files changed, 193 insertions(+), 80 deletions(-)
diff --git a/src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java b/src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java
index d6e739d..d367deb 100644
--- a/src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java
+++ b/src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java
@@ -17,7 +17,20 @@
package org.keycloak.protocol.oidc.utils;
-import org.jboss.logging.Logger;
+import java.net.URI;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.regex.Pattern;
+
+import org.keycloak.OAuth2Constants;
+import org.keycloak.common.util.KeycloakUriBuilder;
+import org.keycloak.common.util.MultivaluedHashMap;
import org.keycloak.common.util.UriUtils;
import org.keycloak.models.ClientModel;
import org.keycloak.models.Constants;
@@ -27,23 +40,32 @@
import org.keycloak.services.Urls;
import org.keycloak.services.util.ResolveRelative;
-import java.net.URI;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.Set;
-import java.util.stream.Collectors;
+import org.jboss.logging.Logger;
/**
* @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
*/
public class RedirectUtils {
- private static final Logger logger = Logger.getLogger(RedirectUtils.class);
+ public static final Set<String> LOOPBACK_INTERFACES = new HashSet<>(Arrays.asList("localhost", "127.0.0.1", "[::1]"));
- public static String verifyRealmRedirectUri(KeycloakSession session, String redirectUri) {
- Set<String> validRedirects = getValidateRedirectUris(session);
- return verifyRedirectUri(session, null, redirectUri, validRedirects, true);
- }
+ private static final Set<String> FORBIDDEN_OIDC_PARAMS = Set.of(
+ OAuth2Constants.CODE,
+ OAuth2Constants.ID_TOKEN,
+ OAuth2Constants.ACCESS_TOKEN,
+ OAuth2Constants.TOKEN_TYPE,
+ OAuth2Constants.EXPIRES_IN,
+ OAuth2Constants.STATE,
+ OAuth2Constants.ISSUER,
+ OAuth2Constants.ERROR,
+ OAuth2Constants.ERROR_DESCRIPTION,
+ OAuth2Constants.SESSION_STATE,
+ OAuth2Constants.RESPONSE,
+ Constants.KC_ACTION,
+ Constants.KC_ACTION_STATUS
+ );
+
+ private static final Logger logger = Logger.getLogger(RedirectUtils.class);
public static String verifyRedirectUri(KeycloakSession session, String redirectUri, ClientModel client) {
return verifyRedirectUri(session, redirectUri, client, true);
@@ -57,44 +79,22 @@
public static Set<String> resolveValidRedirects(KeycloakSession session, String rootUrl, Set<String> validRedirects) {
// If the valid redirect URI is relative (no scheme, host, port) then use the request's scheme, host, and port
- Set<String> resolveValidRedirects = new HashSet<>();
+ // the set is ordered by length to get the longest match first
+ Set<String> resolveValidRedirects = new TreeSet<>((String s1, String s2) -> s1.length() == s2.length()? s1.compareTo(s2) : s1.length() < s2.length()? 1 : -1);
for (String validRedirect : validRedirects) {
if (validRedirect.startsWith("/")) {
validRedirect = relativeToAbsoluteURI(session, rootUrl, validRedirect);
logger.debugv("replacing relative valid redirect with: {0}", validRedirect);
- resolveValidRedirects.add(validRedirect);
- } else {
- resolveValidRedirects.add(validRedirect);
}
+ resolveValidRedirects.add(validRedirect);
}
return resolveValidRedirects;
}
- private static Set<String> getValidateRedirectUris(KeycloakSession session) {
- return session.getContext().getRealm().getClientsStream()
- .filter(ClientModel::isEnabled)
- .map(c -> resolveValidRedirects(session, c.getRootUrl(), c.getRedirectUris()))
- .flatMap(Collection::stream)
- .collect(Collectors.toSet());
- }
-
- private static String verifyRedirectUri(KeycloakSession session, String rootUrl, String redirectUri, Set<String> validRedirects, boolean requireRedirectUri) {
+ public static String verifyRedirectUri(KeycloakSession session, String rootUrl, String redirectUri, Set<String> validRedirects, boolean requireRedirectUri) {
KeycloakUriInfo uriInfo = session.getContext().getUri();
RealmModel realm = session.getContext().getRealm();
- if (redirectUri != null) {
- try {
- URI uri = URI.create(redirectUri);
- redirectUri = uri.normalize().toString();
- } catch (IllegalArgumentException cause) {
- logger.debug("Invalid redirect uri", cause);
- return null;
- } catch (Exception cause) {
- logger.debug("Unexpected error when parsing redirect uri", cause);
- return null;
- }
- }
-
if (redirectUri == null) {
if (!requireRedirectUri) {
redirectUri = getSingleValidRedirectUri(validRedirects);
@@ -108,32 +108,48 @@
logger.debug("No Redirect URIs supplied");
redirectUri = null;
} else {
- redirectUri = lowerCaseHostname(redirectUri);
+ URI originalRedirect = toUri(redirectUri);
+ if (originalRedirect == null) {
+ // invalid URI passed as redirectUri
+ return null;
+ }
+
+ // Check for HTTP Parameter Pollution - forbidden OIDC response parameters in redirect URI
+ if (containsForbiddenOidcParameters(originalRedirect)){
+ return null;
+ }
+
+ // check if the passed URI allows wildcards
+ boolean allowWildcards = areWildcardsAllowed(originalRedirect);
String r = redirectUri;
Set<String> resolveValidRedirects = resolveValidRedirects(session, rootUrl, validRedirects);
- boolean valid = matchesRedirects(resolveValidRedirects, r);
+ String valid = matchesRedirects(resolveValidRedirects, r, allowWildcards);
- if (!valid && r.startsWith(Constants.INSTALLED_APP_URL) && r.indexOf(':', Constants.INSTALLED_APP_URL.length()) >= 0) {
- int i = r.indexOf(':', Constants.INSTALLED_APP_URL.length());
-
- StringBuilder sb = new StringBuilder();
- sb.append(r.substring(0, i));
-
- i = r.indexOf('/', i);
- if (i >= 0) {
- sb.append(r.substring(i));
- }
-
- r = sb.toString();
-
- valid = matchesRedirects(resolveValidRedirects, r);
+ if (valid == null && "http".equals(originalRedirect.getScheme()) && LOOPBACK_INTERFACES.contains(originalRedirect.getHost())) {
+ String redirectWithDefaultPort = KeycloakUriBuilder.fromUri(originalRedirect).port(80).buildAsString();
+ valid = matchesRedirects(resolveValidRedirects, redirectWithDefaultPort, allowWildcards);
}
- if (valid && redirectUri.startsWith("/")) {
+
+ if (valid != null && !originalRedirect.isAbsolute()) {
+ // return absolute if the original URI is relative
+ if (!redirectUri.startsWith("/")) {
+ redirectUri = "/" + redirectUri;
+ }
redirectUri = relativeToAbsoluteURI(session, rootUrl, redirectUri);
}
- redirectUri = valid ? redirectUri : null;
+
+ String scheme = originalRedirect.getScheme();
+ if (valid != null && scheme != null) {
+ // check the scheme is valid, it should be http(s) or explicitly allowed by the validation
+ if (!valid.startsWith(scheme + ":") && !"http".equalsIgnoreCase(scheme) && !"https".equalsIgnoreCase(scheme)) {
+ logger.debugf("Invalid URI because scheme is not allowed: %s", redirectUri);
+ valid = null;
+ }
+ }
+
+ redirectUri = valid != null ? redirectUri : null;
}
if (Constants.INSTALLED_APP_URN.equals(redirectUri)) {
@@ -143,13 +159,50 @@
}
}
- private static String lowerCaseHostname(String redirectUri) {
- int n = redirectUri.indexOf('/', 7);
- if (n == -1) {
- return redirectUri.toLowerCase();
- } else {
- return redirectUri.substring(0, n).toLowerCase() + redirectUri.substring(n);
+ private static boolean containsForbiddenOidcParameters(URI originalRedirect) {
+ String query = originalRedirect.getRawQuery();
+ if (query != null && !query.isEmpty()) {
+ MultivaluedHashMap<String, String> params =UriUtils.decodeQueryString(query);
+ for (String paramName : params.keySet()) {
+ if (FORBIDDEN_OIDC_PARAMS.contains(paramName.toLowerCase(Locale.ROOT))) {
+ logger.warnf("Redirect URI rejected: contains forbidden OIDC parameter '%s' in query string: scheme=%s, host=%s, path=%s",
+ paramName,
+ originalRedirect.getScheme(),
+ originalRedirect.getHost(),
+ originalRedirect.getPath());
+ return true;
+ }
+ }
}
+ return false;
+ }
+
+ private static URI toUri(String redirectUri) {
+ URI uri = null;
+ if (redirectUri != null) {
+ try {
+ uri = URI.create(redirectUri);
+ } catch (IllegalArgumentException cause) {
+ logger.debugf(cause, "Invalid redirect uri %s", redirectUri);
+ } catch (Exception cause) {
+ logger.debugf(cause, "Unexpected error when parsing redirect uri %s", redirectUri);
+ }
+ }
+ return uri;
+ }
+
+ // any access to parent folder /../ is unsafe with or without encoding
+ // <sep> = / | %2F | %5C | \
+ // <dots> = "..", including %2E and %252E (double-encoded) variants
+ // <terminator> = / | %2F | %5C | \ | ; | %3B | %09 | %0A | %0D | %00 | end-of-input
+ private final static Pattern UNSAFE_PATH_PATTERN = Pattern.compile(
+ "(/|%2[fF]|%5[cC]|\\\\)(%2[eE]|%252[eE]|\\.){2}(/|%2[fF]|%5[cC]|\\\\|;|%3[bB]|%09|%0[aAdD]|%00|$)");
+
+ private static boolean areWildcardsAllowed(URI redirectUri) {
+ // wildcars are only allowed if no user-info and no unparsed authority and no unsafe pattern in path
+ return redirectUri.getRawUserInfo() == null
+ && !(redirectUri.getRawAuthority() != null && redirectUri.getRawUserInfo() == null && redirectUri.getHost() == null && redirectUri.getPort() == -1)
+ && (redirectUri.getRawPath() == null || !UNSAFE_PATH_PATTERN.matcher(redirectUri.getRawPath()).find());
}
private static String relativeToAbsoluteURI(KeycloakSession session, String rootUrl, String relative) {
@@ -166,22 +219,66 @@
return sb.toString();
}
- private static boolean matchesRedirects(Set<String> validRedirects, String redirect) {
+ // return the String that matched the redirect or null if not matched
+ private static String matchesRedirects(Set<String> validRedirects, String redirect, boolean allowWildcards) {
+ logger.tracef("matchesRedirects: redirect URL to check: %s, allow wildcards: %b, Configured valid redirect URLs: %s", redirect, allowWildcards, validRedirects);
for (String validRedirect : validRedirects) {
- if (validRedirect.endsWith("*") && !validRedirect.contains("?")) {
- // strip off the query component - we don't check them when wildcards are effective
- String r = redirect.contains("?") ? redirect.substring(0, redirect.indexOf("?")) : redirect;
- // strip off *
- int length = validRedirect.length() - 1;
- validRedirect = validRedirect.substring(0, length);
- if (r.startsWith(validRedirect)) return true;
- // strip off trailing '/'
- if (length - 1 > 0 && validRedirect.charAt(length - 1) == '/') length--;
- validRedirect = validRedirect.substring(0, length);
- if (validRedirect.equals(r)) return true;
- } else if (validRedirect.equals(redirect)) return true;
+ if ("*".equals(validRedirect)) {
+ // the valid redirect * is a full wildcard for http(s) even if the redirect URI does not allow wildcards
+ return validRedirect;
+ } else {
+ String validRedirectWildcard = allowWildcards ? checkValidRedirectWildcard(validRedirect) : null;
+ if (validRedirectWildcard != null) {
+ // strip off the query or fragment components - we don't check them when wildcards are effective
+ int idx = redirect.indexOf('?');
+ if (idx == -1) {
+ idx = redirect.indexOf('#');
+ }
+ String r = idx == -1 ? redirect : redirect.substring(0, idx);
+ // strip off *
+ int length = validRedirectWildcard.length() - 1;
+ validRedirectWildcard = validRedirectWildcard.substring(0, length);
+ if (r.startsWith(validRedirectWildcard)) {
+ return validRedirectWildcard;
+ }
+ // strip off trailing '/'
+ if (length - 1 > 0 && validRedirectWildcard.charAt(length - 1) == '/') {
+ length--;
+ }
+ validRedirectWildcard = validRedirectWildcard.substring(0, length);
+ if (validRedirectWildcard.equals(r)) {
+ return validRedirectWildcard;
+ }
+ } else if (validRedirect.equals(redirect)) {
+ return validRedirect;
+ }
+ }
}
- return false;
+ return null;
+ }
+
+ private static String checkValidRedirectWildcard(String validRedirect) {
+ if (!validRedirect.endsWith("*") || validRedirect.contains("?") || validRedirect.contains("#")) {
+ return null; // no wildcard as before
+ }
+ KeycloakUriBuilder uriBuilder = KeycloakUriBuilder.fromUri(validRedirect, false);
+ if (uriBuilder.getPath() != null) {
+ return validRedirect; // wildcard valid on path
+ }
+ if (uriBuilder.getAuthority() != null) {
+ if (uriBuilder.getAuthority().equals("*") || uriBuilder.getAuthority().endsWith(":*")) {
+ return validRedirect; // on authority just full wildcard or on port
+ } else {
+ // treat the wildcard after the authority
+ validRedirect = validRedirect.substring(0, validRedirect.length() - 1);
+ validRedirect = validRedirect + "/*";
+ return validRedirect;
+ }
+ }
+ if (uriBuilder.getSsp() != null) {
+ return validRedirect; // wildcard valid on SSP
+ }
+ return null;
}
private static String getSingleValidRedirectUri(Collection<String> validRedirects) {
@@ -201,12 +298,28 @@
return redirectUri;
}
- private static String getFirstValidRedirectUri(Collection<String> validRedirects) {
- final String redirectUri = validRedirects.stream().findFirst().orElse(null);
- return (redirectUri != null) ? validateRedirectUriWildcard(redirectUri) : null;
+ public static Set<String> resolveUrlsWithRedirects(KeycloakSession session, List<String> origUrls,
+ String rootUrl, List<String> redirectUris, boolean returnAsOrigins) {
+
+ Set<String> refactoredUrls = (origUrls != null) ? new HashSet<>(origUrls) : new HashSet<>();
+ if (refactoredUrls.contains(Constants.INCLUDE_REDIRECTS)) {
+ refactoredUrls.remove(Constants.INCLUDE_REDIRECTS);
+
+ Set<String> redirectsToProcess = (redirectUris != null) ? new HashSet<>(redirectUris) : Collections.emptySet();
+ for (String redirectUri : resolveValidRedirects(session, rootUrl, redirectsToProcess)) {
+ if (isValidScheme(redirectUri)) {
+ if (returnAsOrigins) {
+ refactoredUrls.add(UriUtils.getOrigin(redirectUri));
+ } else {
+ refactoredUrls.add(redirectUri);
+ }
+ }
+ }
+ }
+ return refactoredUrls;
}
- public static String getFirstValidRedirectUri(KeycloakSession session, String rootUrl, Set<String> validRedirects) {
- return getFirstValidRedirectUri(resolveValidRedirects(session, rootUrl, validRedirects));
+ private static boolean isValidScheme(String url) {
+ return url != null && (url.startsWith("http://") || url.startsWith("https://"));
}
}
--
Gitblit v1.10.0