Low severity · published May 25, 2026
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
3.1
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PU
PuTTY · PuTTY
0.77 before 0.84 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-48851
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-48851
Release Notes
https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html
Patch
https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/telnet-trust-sigil.html
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