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// Copyright 2021 Code Intelligence GmbH
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.code_intelligence.jazzer.sanitizers
import com.code_intelligence.jazzer.api.FuzzerSecurityIssueCritical
import com.code_intelligence.jazzer.api.HookType
import com.code_intelligence.jazzer.api.Jazzer
import com.code_intelligence.jazzer.api.MethodHook
import com.code_intelligence.jazzer.api.MethodHooks
import java.lang.invoke.MethodHandle
import javax.naming.CommunicationException
object NamingContextLookup {
// The particular URL g.co is used here since it is:
// - short, which makes it easier for the fuzzer to incorporate into the input;
// - valid, which means that a `lookup` call on it could actually result in RCE;
// - highly reputable, which makes it very unlikely that it would ever host an actual exploit.
private const val LDAP_MARKER = "ldap://g.co/"
private const val RMI_MARKER = "rmi://g.co/"
@MethodHooks(
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.Context",
targetMethod = "lookup",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialContext",
targetMethod = "lookup",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialDirContext",
targetMethod = "lookup",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialLdapContext",
targetMethod = "lookup",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.Context",
targetMethod = "lookupLink",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialContext",
targetMethod = "lookupLink",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialDirContext",
targetMethod = "lookupLink",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
MethodHook(
type = HookType.REPLACE,
targetClassName = "javax.naming.InitialLdapContext",
targetMethod = "lookupLink",
targetMethodDescriptor = "(Ljava/lang/String;)Ljava/lang/Object;",
),
)
@JvmStatic
fun lookupHook(method: MethodHandle?, thisObject: Any?, args: Array<Any?>, hookId: Int): Any {
val name = args[0] as String
if (name.startsWith(RMI_MARKER) || name.startsWith(LDAP_MARKER)) {
Jazzer.reportFindingFromHook(
FuzzerSecurityIssueCritical(
"""Remote JNDI Lookup
JNDI lookups with attacker-controlled remote URLs can, depending on the JDK
version, lead to remote code execution or the exfiltration of information."""
)
)
}
Jazzer.guideTowardsEquality(name, RMI_MARKER, hookId)
Jazzer.guideTowardsEquality(name, LDAP_MARKER, 31 * hookId)
// Pretend that the remote endpoint could not be reached for additional protection against
// accidental execution of remote code during fuzzing.
throw CommunicationException()
}
}
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