PuTTY vulnerabilities: known CVEs & security history
PuTTY · Remote access · 36 tracked CVEs · 0 actively exploited · updated June 2026 · what is a CVE? →
This is the full list of known vulnerabilities (CVEs) across all PuTTY release lines — 36 in total. A CVE here doesn't mean your version is affected — check PuTTY's current status and the safe version to run.
Known PuTTY CVEs
Actively-exploited and most-severe first. Open any CVE for full details.
| CVE | Severity | CVSS | EPSS | Year |
|---|---|---|---|---|
| CVE-2019-17067 | critical | 9.8 | 2% | 2019 |
| CVE-2019-9898 | critical | 9.8 | 4% | 2019 |
| CVE-2019-9895 | critical | 9.8 | 3% | 2019 |
| CVE-2017-6542 | critical | 9.8 | 22% | 2017 |
| CVE-2004-1008 | high | 10 | 7% | 2005 |
| CVE-2002-1357 | high | 10 | 10% | 2002 |
| CVE-2002-1358 | high | 10 | 6% | 2002 |
| CVE-2002-1359 | high | 10 | 80% | 2002 |
| CVE-2002-1360 | high | 10 | 6% | 2002 |
| CVE-2021-36367 | high | 8.1 | 1% | 2021 |
| CVE-2019-9896 | high | 7.8 | 1% | 2019 |
| CVE-2016-6167 | high | 7.8 | 1% | 2017 |
| CVE-2021-33500 | high | 7.5 | 2% | 2021 |
| CVE-2019-17069 | high | 7.5 | 2% | 2019 |
| CVE-2019-17068 | high | 7.5 | 2% | 2019 |
| CVE-2019-9897 | high | 7.5 | 3% | 2019 |
| CVE-2019-9894 | high | 7.5 | 2% | 2019 |
| CVE-2005-0467 | high | 7.5 | 4% | 2005 |
| CVE-2004-1440 | high | 7.5 | 4% | 2004 |
| CVE-2003-0069 | high | 7.5 | 2% | 2003 |
| CVE-2013-4852 | medium | 6.8 | 3% | 2013 |
| CVE-2013-4206 | medium | 6.8 | 2% | 2013 |
| CVE-2024-31497 | medium | 5.9 | 6% | 2024 |
| CVE-2023-48795 | medium | 5.9 | 93% | 2023 |
| CVE-2020-14002 | medium | 5.9 | 3% | 2020 |
| CVE-2000-0476 | medium | 5 | 3% | 2000 |
| CVE-2003-0048 | medium | 4.6 | 0% | 2003 |
| CVE-2013-4207 | medium | 4.3 | 2% | 2013 |
| CVE-2026-48852 | low | 3.7 | 0% | 2026 |
| CVE-2026-48850 | low | 3.7 | 0% | 2026 |
| CVE-2026-4115 | low | 3.7 | 1% | 2026 |
| CVE-2026-48851 | low | 3.1 | 0% | 2026 |
| CVE-2015-2157 | low | 2.1 | 1% | 2015 |
| CVE-2011-4607 | low | 2.1 | 0% | 2013 |
| CVE-2013-4208 | low | 2.1 | 0% | 2013 |
| CVE-2006-7162 | low | 1.9 | 0% | 2007 |
Is my PuTTY version affected?
The list above spans every release. To know whether your version is affected — and the minimum safe version to upgrade to — check it directly.
Check your PuTTY version → · Monitor PuTTY for new CVEs →
PuTTY vulnerabilities — frequently asked
How many known vulnerabilities does PuTTY have?
IsItPatched tracks 36 CVEs for PuTTY. 4 are critical-severity and 16 high-severity. These span every release line — what matters is whether the version you run is affected.
Does PuTTY have any actively-exploited vulnerabilities?
None of PuTTY's tracked CVEs are currently in CISA's KEV catalog — but new ones can be added at any time, so keep your version current.
What is the most severe PuTTY vulnerability?
Among tracked issues, CVE-2019-17067 (CRITICAL, CVSS 9.8) ranks highest — a Resource exhaustion weakness.
Is PuTTY safe to use?
It depends on the version. The latest supported PuTTY release clears the known issues; older versions may still be affected. Check the exact version you run for a verdict.
CVE data aggregated from NVD, CISA KEV and EPSS (FIRST.org). Related: PuTTY security status · PuTTY end-of-life · actively-exploited CVEs. Always verify against PuTTY's advisories — see our disclaimer.