CVE-2026-48850
CVE-2026-48850 is a low-severity vulnerability in Putty with a CVSS 3.x base score of 3.7. 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-415.
Key facts
- Severity: Low (CVSS 3.x base score 3.7)
- EPSS exploit prediction: 0% (24th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-31729
- Weakness: CWE-415
- Affected product: Putty
- Published:
- Last modified:
Description
PuTTY 0.72 before 0.84 has a double free in RSA KEX.
Frequently asked questions
- What is CVE-2026-48850?
- PuTTY 0.72 before 0.84 has a double free in RSA KEX.
- How severe is CVE-2026-48850?
- CVE-2026-48850 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
- Is CVE-2026-48850 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-48850?
- CVE-2026-48850 affects Putty. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-48850?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-48850 have an EU (EUVD) identifier?
- Yes. CVE-2026-48850 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31729.
- When was CVE-2026-48850 published?
- CVE-2026-48850 was published on 2026-05-25 and last updated on 2026-06-17.
References
- https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html
- https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/rsakex-double-free.html
Affected products (1)
- cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*
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