When using the Apache JServ Protocol (AJP), care must be taken when trusting incoming connections to Apache Tomcat. Tomcat treats AJP connections as having higher trust than, for example, a similar HTTP connection. If such connections are available to an attacker, they can be exploited in ways that may be surprising. In Apache Tomcat 9.0.0.M1 to 9.0.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99, Tomcat shipped with an AJP Connector enabled by default that listened on all configured IP addresses. It was expected (and recommended in the security guide) that this Connector would be disabled if not required. This vulnerability report identified a mechanism that allowed: - returning arbitrary files from anywhere in the web application - processing any file in the web application as a JSP Further, if the web application allowed file upload and stored those files within the web application (or the attacker was able to control the content of the web application by some other means) then this, along with the ability to process a file as a JSP, made remote code execution possible. It is important to note that mitigation is only required if an AJP port is accessible to untrusted users. Users wishing to take a defence-in-depth approach and block the vector that permits returning arbitrary files and execution as JSP may upgrade to Apache Tomcat 9.0.31, 8.5.51 or 7.0.100 or later. A number of changes were made to the default AJP Connector configuration in 9.0.31 to harden the default configuration. It is likely that users upgrading to 9.0.31, 8.5.51 or 7.0.100 or later will need to make small changes to their configurations.
case Constants.SC_A_REQ_ATTRIBUTE : requestHeaderMessage.getBytes(tmpMB); String n = tmpMB.toString(); requestHeaderMessage.getBytes(tmpMB); String v = tmpMB.toString(); /* * AJP13 misses to forward the local IP address and the * remote port. Allow the AJP connector to add this info via * private request attributes. * We will accept the forwarded data and remove it from the * public list of request attributes. */ if(n.equals(Constants.SC_A_REQ_LOCAL_ADDR)) { // 赋值IP给request request.localAddr().setString(v); } elseif(n.equals(Constants.SC_A_REQ_REMOTE_PORT)) { // 赋值端口给request try { request.setRemotePort(Integer.parseInt(v)); } catch (NumberFormatException nfe) { // Ignore invalid value } } elseif(n.equals(Constants.SC_A_SSL_PROTOCOL)) { // 将https属性加入key中 request.setAttribute(SSLSupport.PROTOCOL_VERSION_KEY, v); } else { // 其他情况直接加入key - request.setAttribute(n, v ); // All 'known' attributes will be processed by the previous // blocks. Any remaining attribute is an 'arbitrary' one. + Pattern pattern = protocol.getAllowedArbitraryRequestAttributesPattern(); + if (pattern == null) { + response.setStatus(403); + setErrorState(ErrorState.CLOSE_CLEAN, null); + } else { + Matcher m = pattern.matcher(n); + if (m.matches()) { + request.setAttribute(n, v); + } else { + response.setStatus(403); + setErrorState(ErrorState.CLOSE_CLEAN, null); + } + } } break;
619 if (method.equals(METHOD_GET)) { long lastModified = getLastModified(req); if (lastModified == -1) { // servlet doesn't support if-modified-since, no reason // to go through further expensive logic doGet(req, resp); } else { long ifModifiedSince; try { ifModifiedSince = req.getDateHeader(HEADER_IFMODSINCE); } catch (IllegalArgumentException iae) { // Invalid date header - proceed as if none was set ifModifiedSince = -1; } if (ifModifiedSince < (lastModified / 1000 * 1000)) { // If the servlet mod time is later, call doGet() // Round down to the nearest second for a proper compare // A ifModifiedSince of -1 will always be less maybeSetLastModified(resp, lastModified); doGet(req, resp); } else { resp.setStatus(HttpServletResponse.SC_NOT_MODIFIED); } } }
