Vulnerability in Putty
CVE-2026-48851
PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (18.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 18.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Putty — versions 0.77
Weakness classification (CWE)
References
- lists.tartarus.org/pipermail/putty-announce/2026/000042.html (Release Notes)
- www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/telnet-trust-sigil.html (Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-48851?
- CVE-2026-48851 is a low-severity vulnerability in Putty, classified under User Interface (UI) Misrepresentation of Critical Information. CVSS score: 3.1/10. Published 2026-05-25.
- How severe is CVE-2026-48851?
- Low severity. CVSS v3 base score is 3.1 out of 10.