How severe is CVE-2026-48851?

CVE-2026-48851 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-48851 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-48851?

CVE-2026-48851 affects Putty. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-48851?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-48851 have an EU (EUVD) identifier?

Yes. CVE-2026-48851 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31731.

When was CVE-2026-48851 published?

CVE-2026-48851 was published on 2026-05-25 and last updated on 2026-06-17.

CVE-2026-48851

CVE-2026-48851 is a low-severity vulnerability in Putty with a CVSS 3.x base score of 3.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-451.

Key facts

Severity: Low (CVSS 3.x base score 3.1)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31731
Weakness: CWE-451
Affected product: Putty
Published: 2026-05-25
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-48851?: CVE-2026-48851 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-48851 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-48851?: CVE-2026-48851 affects Putty. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-48851?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-48851 have an EU (EUVD) identifier?: Yes. CVE-2026-48851 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31731.
When was CVE-2026-48851 published?: CVE-2026-48851 was published on 2026-05-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*

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