Summary
Log injection in SimpleSAMLphp
Background
SimpleSAMLphp has a logging functionality that allows system administrators to keep track of the activity, errors, and statistics. Additionally, it allows users to report errors, shall they happen. An error report contains a report identifier, which is logged once submitted.
Description
The www/erroreport.php script, which receives error reports and sends them via email to the system administrator, didn't properly sanitize the report identifier obtained from the request. This allows an attacker, under specific circumstances, to inject new log lines by manually crafting this report ID.
When configured to use the file logging handler, SimpleSAMLphp will output all its logs by appending each log line to a given file. Since the reportID parameter received in a request sent to www/errorreport.php was not properly sanitized, it was possible to inject newline characters into it, effectively allowing a malicious user to inject new log lines with arbitrary content.
Affected versions
SimpleSAMLphp versions up to 1.18.3.
Resolution
Upgrade the SimpleSAMLphp installation to version 1.18.4.
Credit
This vulnerability was discovered and reported by Frederic Vleminckx on January 23, 2020.
Impact
An attacker may use this issue to inject logs messages into a SimpleSAMLphp log file, trying to trick or confuse system administrators. However, the attack surface is considered small, as the attack will only work with the file logging handler, which opens the log file in append-only mode. This means an attacker cannot edit or remove existing log messages, and even if non-ascii characters are written to the log, the file will always be readable with a simple text editor.
CVE-2020-5225 has a CVSS score of 4.4 (Low). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.18.4); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2020-5225? CVE-2020-5225 is a low-severity security vulnerability in simplesamlphp/simplesamlphp (composer), affecting versions < 1.18.4. It is fixed in 1.18.4.
- How severe is CVE-2020-5225? CVE-2020-5225 has a CVSS score of 4.4 (Low). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of simplesamlphp/simplesamlphp are affected by CVE-2020-5225? simplesamlphp/simplesamlphp (composer) versions < 1.18.4 is affected.
- Is there a fix for CVE-2020-5225? Yes. CVE-2020-5225 is fixed in 1.18.4. Upgrade to this version or later.
- Is CVE-2020-5225 exploitable, and should I be worried? Whether CVE-2020-5225 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2020-5225 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2020-5225? Upgrade
simplesamlphp/simplesamlphpto 1.18.4 or later.