diff --git a/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.java b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.java new file mode 100644 index 00000000000..48d80707ff8 --- /dev/null +++ b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.java @@ -0,0 +1,44 @@ +class SensitiveCookieNotHttpOnly { + // GOOD - Create a sensitive cookie with the `HttpOnly` flag set. + public void addCookie(String jwt_token, HttpServletRequest request, HttpServletResponse response) { + Cookie jwtCookie =new Cookie("jwt_token", jwt_token); + jwtCookie.setPath("/"); + jwtCookie.setMaxAge(3600*24*7); + jwtCookie.setHttpOnly(true); + response.addCookie(jwtCookie); + } + + // BAD - Create a sensitive cookie without the `HttpOnly` flag set. + public void addCookie2(String jwt_token, String userId, HttpServletRequest request, HttpServletResponse response) { + Cookie jwtCookie =new Cookie("jwt_token", jwt_token); + jwtCookie.setPath("/"); + jwtCookie.setMaxAge(3600*24*7); + response.addCookie(jwtCookie); + } + + // GOOD - Set a sensitive cookie header with the `HttpOnly` flag set. + public void addCookie3(String authId, HttpServletRequest request, HttpServletResponse response) { + response.addHeader("Set-Cookie", "token=" +authId + ";HttpOnly;Secure"); + } + + // BAD - Set a sensitive cookie header without the `HttpOnly` flag set. + public void addCookie4(String authId, HttpServletRequest request, HttpServletResponse response) { + response.addHeader("Set-Cookie", "token=" +authId + ";Secure"); + } + + // GOOD - Set a sensitive cookie header using the class `javax.ws.rs.core.Cookie` with the `HttpOnly` flag set through string concatenation. + public void addCookie5(String accessKey, HttpServletRequest request, HttpServletResponse response) { + response.setHeader("Set-Cookie", new NewCookie("session-access-key", accessKey, "/", null, null, 0, true) + ";HttpOnly"); + } + + // BAD - Set a sensitive cookie header using the class `javax.ws.rs.core.Cookie` without the `HttpOnly` flag set. + public void addCookie6(String accessKey, HttpServletRequest request, HttpServletResponse response) { + response.setHeader("Set-Cookie", new NewCookie("session-access-key", accessKey, "/", null, null, 0, true).toString()); + } + + // GOOD - Set a sensitive cookie header using the class `javax.ws.rs.core.Cookie` with the `HttpOnly` flag set through the constructor. + public void addCookie7(String accessKey, HttpServletRequest request, HttpServletResponse response) { + NewCookie accessKeyCookie = new NewCookie("session-access-key", accessKey, "/", null, null, 0, true, true); + response.setHeader("Set-Cookie", accessKeyCookie.toString()); + } +} diff --git a/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.qhelp b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.qhelp new file mode 100644 index 00000000000..ee3e8a4181a --- /dev/null +++ b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.qhelp @@ -0,0 +1,27 @@ + + + + +

Cross-Site Scripting (XSS) is categorized as one of the OWASP Top 10 Security Vulnerabilities. The HttpOnly flag directs compatible browsers to prevent client-side script from accessing cookies. Including the HttpOnly flag in the Set-Cookie HTTP response header for a sensitive cookie helps mitigate the risk associated with XSS where an attacker's script code attempts to read the contents of a cookie and exfiltrate information obtained.

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Use the HttpOnly flag when generating a cookie containing sensitive information to help mitigate the risk of client side script accessing the protected cookie.

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The following example shows two ways of generating sensitive cookies. In the 'BAD' cases, the HttpOnly flag is not set. In the 'GOOD' cases, the HttpOnly flag is set.

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  • + PortSwigger: + Cookie without HttpOnly flag set +
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  • + OWASP: + HttpOnly +
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    diff --git a/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.ql b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.ql new file mode 100644 index 00000000000..d2d596c23fa --- /dev/null +++ b/java/ql/src/Security/CWE/CWE-1004/SensitiveCookieNotHttpOnly.ql @@ -0,0 +1,223 @@ +/** + * @name Sensitive cookies without the HttpOnly response header set + * @description Sensitive cookies without the 'HttpOnly' flag set leaves session cookies vulnerable to + * an XSS attack. + * @kind path-problem + * @problem.severity warning + * @precision medium + * @id java/sensitive-cookie-not-httponly + * @tags security + * external/cwe/cwe-1004 + */ + +/* + * Sketch of the structure of this query: we track cookie names that appear to be sensitive + * (e.g. `session` or `token`) to a `ServletResponse.addHeader(...)` or `.addCookie(...)` + * method that does not set the `httpOnly` flag. Subsidiary configurations + * `MatchesHttpOnlyConfiguration` and `SetHttpOnlyInCookieConfiguration` are used to establish + * when the `httpOnly` flag is likely to have been set, before configuration + * `MissingHttpOnlyConfiguration` establishes that a non-`httpOnly` cookie has a sensitive-seeming name. + */ + +import java +import semmle.code.java.dataflow.FlowSteps +import semmle.code.java.frameworks.Servlets +import semmle.code.java.dataflow.TaintTracking +import MissingHttpOnlyFlow::PathGraph + +/** Gets a regular expression for matching common names of sensitive cookies. */ +string getSensitiveCookieNameRegex() { result = "(?i).*(auth|session|token|key|credential).*" } + +/** Gets a regular expression for matching CSRF cookies. */ +string getCsrfCookieNameRegex() { result = "(?i).*(csrf).*" } + +/** + * Holds if a string is concatenated with the name of a sensitive cookie. Excludes CSRF cookies since + * they are special cookies implementing the Synchronizer Token Pattern that can be used in JavaScript. + */ +predicate isSensitiveCookieNameExpr(Expr expr) { + exists(string s | s = expr.(CompileTimeConstantExpr).getStringValue() | + s.regexpMatch(getSensitiveCookieNameRegex()) and not s.regexpMatch(getCsrfCookieNameRegex()) + ) + or + isSensitiveCookieNameExpr(expr.(AddExpr).getAnOperand()) +} + +/** A sensitive cookie name. */ +class SensitiveCookieNameExpr extends Expr { + SensitiveCookieNameExpr() { isSensitiveCookieNameExpr(this) } +} + +/** A method call that sets a `Set-Cookie` header. */ +class SetCookieMethodCall extends MethodCall { + SetCookieMethodCall() { + ( + this.getMethod() instanceof ResponseAddHeaderMethod or + this.getMethod() instanceof ResponseSetHeaderMethod + ) and + this.getArgument(0).(CompileTimeConstantExpr).getStringValue().toLowerCase() = "set-cookie" + } +} + +/** + * A taint configuration tracking flow from the text `httponly` to argument 1 of + * `SetCookieMethodCall`. + */ +module MatchesHttpOnlyConfig implements DataFlow::ConfigSig { + predicate isSource(DataFlow::Node source) { + source.asExpr().(CompileTimeConstantExpr).getStringValue().toLowerCase().matches("%httponly%") + } + + predicate isSink(DataFlow::Node sink) { + sink.asExpr() = any(SetCookieMethodCall ma).getArgument(1) + } +} + +module MatchesHttpOnlyFlow = TaintTracking::Global; + +/** A class descended from `javax.servlet.http.Cookie`. */ +class CookieClass extends RefType { + CookieClass() { this.getAnAncestor().hasQualifiedName("javax.servlet.http", "Cookie") } +} + +/** Holds if `expr` is any boolean-typed expression other than literal `false`. */ +// Inlined because this could be a very large result set if computed out of context +pragma[inline] +predicate mayBeBooleanTrue(Expr expr) { + expr.getType() instanceof BooleanType and + not expr.(CompileTimeConstantExpr).getBooleanValue() = false +} + +/** Holds if the method call may set the `HttpOnly` flag. */ +predicate setsCookieHttpOnly(MethodCall ma) { + ma.getMethod().getName() = "setHttpOnly" and + // any use of setHttpOnly(x) where x isn't false is probably safe + mayBeBooleanTrue(ma.getArgument(0)) +} + +/** Holds if `ma` removes a cookie. */ +predicate removesCookie(MethodCall ma) { + ma.getMethod().getName() = "setMaxAge" and + ma.getArgument(0).(IntegerLiteral).getIntValue() = 0 +} + +/** + * Holds if the MethodCall `ma` is a test method call indicated by: + * a) in a test directory such as `src/test/java` + * b) in a test package whose name has the word `test` + * c) in a test class whose name has the word `test` + * d) in a test class implementing a test framework such as JUnit or TestNG + */ +predicate isTestMethod(MethodCall ma) { + exists(Method m | + m = ma.getEnclosingCallable() and + ( + m.getDeclaringType().getName().toLowerCase().matches("%test%") or // Simple check to exclude test classes to reduce FPs + m.getDeclaringType().getPackage().getName().toLowerCase().matches("%test%") or // Simple check to exclude classes in test packages to reduce FPs + exists(m.getLocation().getFile().getAbsolutePath().indexOf("/src/test/java")) or // Match test directory structure of build tools like maven + m instanceof TestMethod // Test method of a test case implementing a test framework such as JUnit or TestNG + ) + ) +} + +/** + * A taint configuration tracking flow of a method that sets the `HttpOnly` flag, + * or one that removes a cookie, to a `ServletResponse.addCookie` call. + */ +module SetHttpOnlyOrRemovesCookieConfig implements DataFlow::ConfigSig { + predicate isSource(DataFlow::Node source) { + source.asExpr() = + any(MethodCall ma | setsCookieHttpOnly(ma) or removesCookie(ma)).getQualifier() + } + + predicate isSink(DataFlow::Node sink) { + sink.asExpr() = + any(MethodCall ma | ma.getMethod() instanceof ResponseAddCookieMethod).getArgument(0) + } +} + +module SetHttpOnlyOrRemovesCookieFlow = TaintTracking::Global; + +/** + * A cookie that is added to an HTTP response and which doesn't have `httpOnly` set, used as a sink + * in `MissingHttpOnlyConfiguration`. + */ +class CookieResponseSink extends DataFlow::ExprNode { + CookieResponseSink() { + exists(MethodCall ma | + ( + ma.getMethod() instanceof ResponseAddCookieMethod and + this.getExpr() = ma.getArgument(0) and + not SetHttpOnlyOrRemovesCookieFlow::flowTo(this) + or + ma instanceof SetCookieMethodCall and + this.getExpr() = ma.getArgument(1) and + not MatchesHttpOnlyFlow::flowTo(this) // response.addHeader("Set-Cookie", "token=" +authId + ";HttpOnly;Secure") + ) and + not isTestMethod(ma) // Test class or method + ) + } +} + +/** Holds if `cie` is an invocation of a JAX-RS `NewCookie` constructor that sets `HttpOnly` to true. */ +predicate setsHttpOnlyInNewCookie(ClassInstanceExpr cie) { + cie.getConstructedType().hasQualifiedName(["javax.ws.rs.core", "jakarta.ws.rs.core"], "NewCookie") and + ( + cie.getNumArgument() = 6 and + mayBeBooleanTrue(cie.getArgument(5)) // NewCookie(Cookie cookie, String comment, int maxAge, Date expiry, boolean secure, boolean httpOnly) + or + cie.getNumArgument() = 8 and + cie.getArgument(6).getType() instanceof BooleanType and + mayBeBooleanTrue(cie.getArgument(7)) // NewCookie(String name, String value, String path, String domain, String comment, int maxAge, boolean secure, boolean httpOnly) + or + cie.getNumArgument() = 10 and + mayBeBooleanTrue(cie.getArgument(9)) // NewCookie(String name, String value, String path, String domain, int version, String comment, int maxAge, Date expiry, boolean secure, boolean httpOnly) + ) +} + +/** + * A taint configuration tracking flow from a sensitive cookie without the `HttpOnly` flag + * set to its HTTP response. + */ +module MissingHttpOnlyConfig implements DataFlow::ConfigSig { + predicate isSource(DataFlow::Node source) { source.asExpr() instanceof SensitiveCookieNameExpr } + + predicate isSink(DataFlow::Node sink) { sink instanceof CookieResponseSink } + + predicate isBarrier(DataFlow::Node node) { + // JAX-RS's `new NewCookie("session-access-key", accessKey, "/", null, null, 0, true, true)` and similar + setsHttpOnlyInNewCookie(node.asExpr()) + } + + predicate isAdditionalFlowStep(DataFlow::Node pred, DataFlow::Node succ) { + exists( + ConstructorCall cc // new Cookie(...) + | + cc.getConstructedType() instanceof CookieClass and + pred.asExpr() = cc.getAnArgument() and + succ.asExpr() = cc + ) + or + exists( + MethodCall ma // cookie.toString() + | + ma.getMethod().getName() = "toString" and + ma.getQualifier().getType() instanceof CookieClass and + pred.asExpr() = ma.getQualifier() and + succ.asExpr() = ma + ) + } +} + +module MissingHttpOnlyFlow = TaintTracking::Global; + +deprecated query predicate problems( + DataFlow::Node sinkNode, MissingHttpOnlyFlow::PathNode source, MissingHttpOnlyFlow::PathNode sink, + string message1, DataFlow::Node sourceNode, string message2 +) { + MissingHttpOnlyFlow::flowPath(source, sink) and + sinkNode = sink.getNode() and + message1 = "$@ doesn't have the HttpOnly flag set." and + sourceNode = source.getNode() and + message2 = "This sensitive cookie" +}