CVE-2020-24034
CWE-502Published: September 1, 2020· Updated: Jun 17, 2026
Official Description
Sagemcom F@ST 5280 routers using firmware version 1.150.61 have insecure deserialization that allows any authenticated user to perform a privilege escalation to any other user. By making a request with valid sess_id, nonce, and ha1 values inside of the serialized session cookie, an attacker may alter the user value inside of this cookie, and assume the role and permissions of the user specified. By assuming the role of the user internal, which is inaccessible to end users by default, the attacker gains the permissions of the internal account, which includes the ability to flash custom firmware to the router, allowing the attacker to achieve a complete compromise.
Technical Analysis
CVE-2020-24034 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.
From a weakness classification perspective (CWE-502): Insecure deserialization vulnerabilities allow attackers to inject malicious objects during deserialization, potentially enabling remote code execution.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (8)
Quick Facts
Related CVEs (CWE-502)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2020-24034 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts