CVE-2019-9895
CVE-2019-9895 is a critical-severity vulnerability in Putty with a CVSS 3.x base score of 9.8. 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-119.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 3% (83rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Putty
- Published:
- Last modified:
Description
In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding.
Frequently asked questions
- What is CVE-2019-9895?
- In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding.
- How severe is CVE-2019-9895?
- CVE-2019-9895 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2019-9895 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-9895?
- CVE-2019-9895 primarily affects Putty. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-9895?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2019-9895 published?
- CVE-2019-9895 was published on 2019-03-21 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00004.html
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00020.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36LWQ3NPFIV7DC7TC4KFPRYRH2OR7SZ2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LDO3F267P347E6U2IILFCYW7JPTLCCES/
- https://seclists.org/bugtraq/2019/Apr/6
- https://security.netapp.com/advisory/ntap-20190404-0001/
- https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html
- https://www.debian.org/security/2019/dsa-4423
Affected products (3)
- cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
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