CVE-2026-79312
MediumCVSS 6.8Exploitation Probability (EPSS)
Low risk33th percentile - higher than 33% of all known CVEs
Summary
webpy web.py 0.76 is vulnerable to Session Fixation. The Session._load() component reads session_id directly from the request cookie and loads that session from the store, and _save() writes back under the same session_id; there is no rotation after authentication, so a fixed session_id keeps the authenticated state.
Risk Assessment
An attacker can fix a victim's session ID and after the victim logs in, hijack the session to access protected resources. The risk is high in applications using web.py for authentication.
Recommendation
Update web.py to a version containing the fix or implement session ID rotation after successful authentication. Consider using an alternative framework if no fix is available.
Other vulnerabilities in web.py
See all- CVE-2026-79313Critical
webpy web.py 0.76 is vulnerable to Insufficient Session Expiration. The application's session management relies on periodic cleanup to expire sessions instead of checking the last-access time when a session is loaded. As a result, an expired session whose record has not yet been cleaned up can still be replayed and used, allowing an attacker holding a previously valid session cookie to continue accessing protected resources after the configured idle timeout.
- CVE-2026-79310High
webpy web.py 0.76 is vulnerable to server-side template injection (SSTI). When an application precompiles templates from a directory the attacker can write to and later renders them through the precompiled template loader, the sandbox is bypassed, allowing arbitrary Python code execution and OS command execution on the server.
- CVE-2026-79311Medium
webpy web.py 0.76 is vulnerable to Cross Site Scripting (XSS) via render_jinja.__init__().
Original NVD description (English source)
webpy web.py 0.76 is vulnerable to Session Fixation. The component Session._load() reads session_id directly from the request cookie and loads that session from the store, and _save() writes back under the same session_id; no rotation after authentication, so a fixed session_id keeps the authenticated state.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS