CVE-2020-17510
📋 TL;DR
CVE-2020-17510 is an authentication bypass vulnerability in Apache Shiro when used with Spring. A specially crafted HTTP request can bypass authentication mechanisms, allowing unauthorized access to protected resources. This affects Apache Shiro versions before 1.7.0 when integrated with Spring applications.
💻 Affected Systems
- Apache Shiro
📦 What is this software?
Shiro by Apache
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise where attackers gain administrative access to the application, potentially leading to data theft, privilege escalation, and full control over affected systems.
Likely Case
Unauthorized access to sensitive application functionality and data, potentially exposing user information, internal business logic, or allowing data manipulation.
If Mitigated
Limited impact with proper network segmentation, strong authentication mechanisms beyond Shiro, and comprehensive logging/monitoring in place.
🎯 Exploit Status
Exploitation requires sending specially crafted HTTP requests. Multiple proof-of-concept examples are publicly available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.7.0 and later
Vendor Advisory: https://lists.apache.org/thread.html/r95bdf3703858b5f958b5e190d747421771b430d97095880db91980d6@%3Cannounce.apache.org%3E
Restart Required: Yes
Instructions:
1. Update Apache Shiro dependency to version 1.7.0 or later. 2. Update pom.xml or build.gradle to reference the new version. 3. Rebuild and redeploy the application. 4. Restart application servers.
🔧 Temporary Workarounds
Request Filtering
allImplement custom request filters to block suspicious HTTP requests that might exploit the vulnerability
Additional Authentication Layer
allAdd secondary authentication mechanisms independent of Shiro for critical endpoints
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to block malicious requests targeting Shiro endpoints
- Isolate affected applications behind additional authentication gateways or reverse proxies
🔍 How to Verify
Check if Vulnerable:
Check Shiro version in application dependencies. If using Maven: mvn dependency:tree | grep shiro. If using Gradle: gradle dependencies | grep shiro.Check Version:
For Java applications: java -cp shiro-core-*.jar org.apache.shiro.util.VersionVerify Fix Applied:
Verify Shiro version is 1.7.0 or higher in dependency management files and deployed application.📡 Detection & Monitoring
Log Indicators:
- Unusual authentication bypass patterns
- Requests with crafted headers targeting Shiro endpoints
- Failed authentication attempts followed by successful access
Network Indicators:
- HTTP requests with specially crafted headers to bypass authentication
- Unusual traffic patterns to protected endpoints without proper authentication
SIEM Query:
source="application_logs" AND ("authentication bypass" OR "shiro" AND "unauthorized access")🔗 References
- https://lists.apache.org/thread.html/r575301804bfac87a064359cf4b4ae9d514f2d10db7d44120765f4129%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r70098e336d02047ce4d4e69293fe8d558cd68cde06f6430398959bc4%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r70b907ccb306e9391145e2b10f56cc6914a245f91720a17a486c020a%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r852971e28f54cafa7d325bd7033115c67d613b112a2a1076817390ac%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r95bdf3703858b5f958b5e190d747421771b430d97095880db91980d6%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r9d93dfb5df016b1a71a808486bc8f9fbafebbdbc8533625f91253f1d%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/rb47d88af224e396ee34ffb88ee99fb6d04510de5722cf14b7137e6bc%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/rc2cff2538b683d480426393eecf1ce8dd80e052fbef49303b4f47171%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/re25b8317b00a50272a7252c4552cf1a81a97984cc2111ef7728e48e0%40%3Cdev.shiro.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2021/08/msg00002.html
- https://lists.apache.org/thread.html/r575301804bfac87a064359cf4b4ae9d514f2d10db7d44120765f4129%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r70098e336d02047ce4d4e69293fe8d558cd68cde06f6430398959bc4%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r70b907ccb306e9391145e2b10f56cc6914a245f91720a17a486c020a%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r852971e28f54cafa7d325bd7033115c67d613b112a2a1076817390ac%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/r95bdf3703858b5f958b5e190d747421771b430d97095880db91980d6%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r9d93dfb5df016b1a71a808486bc8f9fbafebbdbc8533625f91253f1d%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/rb47d88af224e396ee34ffb88ee99fb6d04510de5722cf14b7137e6bc%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/rc2cff2538b683d480426393eecf1ce8dd80e052fbef49303b4f47171%40%3Cdev.shiro.apache.org%3E
- https://lists.apache.org/thread.html/re25b8317b00a50272a7252c4552cf1a81a97984cc2111ef7728e48e0%40%3Cdev.shiro.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2021/08/msg00002.html
