Source: cve@mitre.org
Cross-site scripting (XSS) vulnerability in inc/lib/lib.base.php in SASHA 0.2.0 allows remote attackers to inject arbitrary web script or HTML via the instructors parameter. NOTE: the original disclosure also mentions the section_title parameter, but this was disputed by the vendor and retracted by the original researcher.
SASHA 0.2.0 is vulnerable to a cross-site scripting (XSS) attack, allowing attackers to inject malicious HTML or JavaScript into web pages. This vulnerability, triggered by the instructors parameter, could lead to session hijacking, data theft, or website defacement if exploited.
Step 1: Payload Delivery: The attacker crafts a malicious URL containing a JavaScript payload within the instructors parameter.
Step 2: Request Submission: The attacker sends the crafted URL to a victim, potentially through phishing, social engineering, or other means.
Step 3: Server Processing: The SASHA application receives the request and processes the instructors parameter, likely displaying its value on a webpage.
Step 4: Malicious Code Execution: The victim's browser renders the webpage, including the attacker's injected JavaScript payload. The browser executes the JavaScript, allowing the attacker to perform actions such as stealing cookies, redirecting the user, or defacing the website.
The vulnerability lies within the inc/lib/lib.base.php file of SASHA 0.2.0. The instructors parameter is not properly sanitized or validated before being displayed on the web page. This allows an attacker to inject arbitrary HTML or JavaScript code into the parameter's value. When a user views a page containing the injected code, their browser executes the malicious script. The root cause is a lack of input validation and output encoding (e.g., HTML escaping) of the instructors parameter's content. The application fails to prevent the insertion of malicious code, leading to the XSS vulnerability.
While no specific APT groups are directly linked to exploiting this specific CVE, XSS vulnerabilities are commonly used by various threat actors for initial access and information gathering. This vulnerability could be leveraged by opportunistic attackers. Not in CISA KEV.
Web server logs: Examine web server access logs for suspicious requests containing JavaScript payloads in the instructors parameter (e.g., <script>, onerror, javascript:).
Network traffic analysis: Monitor network traffic for HTTP requests with potentially malicious payloads in the instructors parameter. Use a web application firewall (WAF) to detect and block malicious requests.
Intrusion Detection System (IDS) signatures: Implement IDS rules to detect XSS attempts targeting the instructors parameter.
Content Security Policy (CSP) violations: Monitor for CSP violations, which can indicate the execution of unauthorized scripts.
Input Validation: Implement robust input validation to sanitize the instructors parameter. This includes filtering out potentially dangerous characters and ensuring the input conforms to expected formats.
Output Encoding: Implement proper output encoding (e.g., HTML escaping) to prevent the browser from interpreting user-supplied data as HTML or JavaScript. This should be applied when displaying the instructors parameter's value on the webpage.
Upgrade: Upgrade to a patched version of SASHA or a completely different, secure application if possible. Since this is an older version, it is likely no longer maintained.
Web Application Firewall (WAF): Deploy a WAF to detect and block XSS attempts.
Content Security Policy (CSP): Implement a CSP to restrict the sources from which the browser can load resources, mitigating the impact of XSS attacks.