Deserialization in Sagemcom F\@st 5280 Router
CVE-2020-24034
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.
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.037 (89.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.037 · newest: 0.037 · change: 0.000
Affected products
- Sagemcom F\@st 5280 Router
- Sagemcom F\@st 5280 Router Firmware — versions 1.150.61
Weakness classification (CWE)
Public proof-of-concept exploits
References
- support.sagemcom.com/fr/haut-debit (Vendor Advisory)
- seclists.org/fulldisclosure/2020/Sep/3 (Mailing List, Third Party Advisory)
- seclists.org/fulldisclosure/2020/Sep/3 (mailing-list, Mailing List, Third Party Advisory)
- packetstormsecurity.com/files/159026/Sagemcom-F-ST-5280-Privilege-Escalation.ht… (Exploit, VDB Entry, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-24034?
- CVE-2020-24034 is a high-severity vulnerability in Sagemcom F\@st 5280 Router, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2020-09-01.
- How severe is CVE-2020-24034?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2020-24034 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.