CVE-2019-9897
CVE-2019-9897 is a high-severity vulnerability in Putty with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 3% (86th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Putty
- Published:
- Last modified:
Description
Multiple denial-of-service attacks that can be triggered by writing to the terminal exist in PuTTY versions before 0.71.
Frequently asked questions
- What is CVE-2019-9897?
- Multiple denial-of-service attacks that can be triggered by writing to the terminal exist in PuTTY versions before 0.71.
- How severe is CVE-2019-9897?
- CVE-2019-9897 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2019-9897 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-9897?
- CVE-2019-9897 primarily affects Putty. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-9897?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2019-9897 published?
- CVE-2019-9897 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.debian.org/debian-lts-announce/2019/04/msg00023.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 (7)
- cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:a:netapp:oncommand_unified_manager:-:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:leap:15.0:*:*:*:*:*:*:*
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