CVE-2019-3863

CVE-2019-3863 is a high-severity vulnerability in Redhat Enterprise Linux Desktop 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. The underlying weakness is classified as CWE-787.

Key facts

Description

A flaw was found in libssh2 before 1.8.1 creating a vulnerability on the SSH client side. A server could send a multiple keyboard interactive response messages whose total length are greater than unsigned char max characters. This value is used by the SSH client as an index to copy memory causing in an out of bounds memory write error.

Frequently asked questions

What is CVE-2019-3863?
A flaw was found in libssh2 before 1.8.1 creating a vulnerability on the SSH client side. A server could send a multiple keyboard interactive response messages whose total length are greater than unsigned char max characters. This value is used by the SSH client as an index to copy memory causing in an out of bounds memory write error.
How severe is CVE-2019-3863?
CVE-2019-3863 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-3863 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-3863?
CVE-2019-3863 primarily affects Redhat Enterprise Linux Desktop. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-3863?
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-2019-3863 published?
CVE-2019-3863 was published on 2019-03-25 and last updated on 2026-06-17.

References

Affected products (11)

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