What is CVE-2021-35309?

CVE-2021-35309 is a high-severity vulnerability in Samsung Syncthru Web Service, classified under Improper Privilege Management. CVSS score: 7.5/10. Published 2023-08-22.

How severe is CVE-2021-35309?

High severity. CVSS v3 base score is 7.5 out of 10.

Privilege escalation in Samsung Syncthru Web Service

CVE-2021-35309

An issue discovered in Samsung SyncThru Web Service SPL 5.93 06-09-2014 allows attackers to gain escalated privileges via MITM attacks.

Vulnerability class: Privilege Escalation

Published 2023-08-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (42.2th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Samsung Syncthru Web Service — versions 5.93

Weakness classification (CWE)

CWE-269 — Improper Privilege Management

References

security.samsungmobile.com/securityUpdate.smsb (Vendor Advisory)
github.com/mustafa-turgut/cve-subscriptions/tree/main/samsung-stws (Third Party Advisory)

Frequently asked questions

What is CVE-2021-35309?: CVE-2021-35309 is a high-severity vulnerability in Samsung Syncthru Web Service, classified under Improper Privilege Management. CVSS score: 7.5/10. Published 2023-08-22.
How severe is CVE-2021-35309?: High severity. CVSS v3 base score is 7.5 out of 10.