CVE-2023-52951 — A cleartext transmission of sensitive information vulnerability in Synology Note

A cleartext transmission of sensitive information vulnerability in Synology Note Station Client before 2.2.4-703 allows man-in-the-middle attackers to obtain user credential.

01What is this vulnerability?

A cleartext transmission of sensitive information vulnerability in Synology Note Station Client before 2.2.4-703 allows man-in-the-middle attackers to obtain user credential.

02Affected products

No structured affected-product list available — see references below for vendor advisories.

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2026-06-03T14:16:25.870
• Last modified: 2026-07-22T19:10:00.120

09References

• www.synology.com — https://www.synology.com/en-global/releaseNote/NoteStationClient