Description
Integer overflow in the terminal emulator in PuTTY before 0.66 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via an ECH (erase characters) escape sequence with a large parameter value, which triggers a buffer underflow.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | putty | 0.66-1 | — |
| Debian 13 | putty | 0.66-1 | — |
| Debian 12 | putty | 0.66-1 | — |
| Debian 8 | putty | 0.63-10+deb8u1 | DSA-3409-1 |
| Debian 7 | putty | 0.62-9+deb7u3 | DSA-3409-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 6.0 | putty | 0.60+2010-02-20-1+squeeze4 | DLA-347-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | putty | 0.67-1.5 | openSUSE-SU-2024:10374-1 |
Advisories 3
- DLA-347-1 putty - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3409-1 putty - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10374-1 putty-0.67-1.5 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- DSA-3409 vendor-advisory
- FEDORA-2015-3d17682c15 vendor-advisory
- FEDORA-2015-5ad4a1f151 vendor-advisory
- 1034308 vdb-entry
- http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-ech-overflow.html
- GLSA-201606-01 vendor-advisory
- openSUSE-SU-2015:2023 vendor-advisory