CVE-2019-3863 — A flaw was found in libssh2 before 1.8.1. A server could send a multiple keyboard interactive...

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

• Documented patch — bugzilla.redhat.com (NIST National Vulnerability Database)
• Documented patch — www.libssh2.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

1. Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Libssh2 Libssh2, Netapp Ontap Select Deploy Administration Utility…).
2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
3. Apply the fixed version or the patch documented under Remediation.
4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
5. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-787 · Out-of-bounds Write

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 3.44%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

• Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
• Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

Timeline

What happened to this CVE, newest first.

• 2026
• Affected products added · the libssh2 project/libssh2
  Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
• SSVC assessment updated
  Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
• Record published
  Oct 14, 2026
• Fix documented
  Oct 14, 2026 · NIST National Vulnerability Database
• Affected products added · libssh2/libssh2, debian/debian linux, netapp/ontap select deploy administration utility, opensuse/leap, redhat/enterpris
  Oct 14, 2026 · NIST National Vulnerability Database
• CVSS changed · 8.8
  Oct 14, 2026 · NIST National Vulnerability Database
• Source status changed · → Modified
  Oct 14, 2026 · NIST National Vulnerability Database
• Record created in this database
  Oct 14, 2026 · Alertas do Telegram
• 2019
• CVE published
  Mar 25, 2019 · redhat

Source activity

Repeated readings are counted rather than listed.

• 2× References added · Oct 14, 2026 – Oct 14, 2026
• 1× Official description updated · Oct 14, 2026 – Oct 14, 2026

References

22 on the record

• bugzilla.redhat.com/show_bug.cgi
  Issue Tracking, Patch, Third Party Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database
• www.libssh2.org/CVE-2019-3863.html
  Patch, Vendor Advisory, x_refsource_MISC, NIST National Vulnerability Database
• security.netapp.com/advisory/ntap-20190327-0005
  GitHub Security Advisories
• access.redhat.com/errata/RHSA-2019:1791
  vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
  x_refsource_MISC, NIST National Vulnerability Database
• lists.opensuse.org/opensuse-security-announce/2019-04/msg00003.html
  Third Party Advisory, vendor-advisory, x_refsource_SUSE, NIST National Vulnerability Database
• security.netapp.com/advisory/ntap-20190327-0005/
  Third Party Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database
• nvd.nist.gov/vuln/detail/CVE-2019-3863
  GitHub Security Advisories
• access.redhat.com/errata/RHSA-2019:0679
  Third Party Advisory, vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5DK6VO
  GitHub Security Advisories
• access.redhat.com/errata/RHSA-2019:1943
  vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6
  vendor-advisory, x_refsource_FEDORA, NIST National Vulnerability Database
• seclists.org/bugtraq/2019/Apr/25
  mailing-list, x_refsource_BUGTRAQ, NIST National Vulnerability Database
• lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5DK6
  GitHub Security Advisories
• cert-portal.siemens.com/productcert/html/ssa-398330.html
  NIST National Vulnerability Database
• github.com/advisories/GHSA-h63q-2463-x5hq
  GitHub Security Advisories
• lists.debian.org/debian-lts-announce/2019/03/msg00032.html
  Mailing List, Third Party Advisory, mailing-list, x_refsource_MLIST, NIST National Vulnerability Database
• access.redhat.com/errata/RHSA-2019:1175
  vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• access.redhat.com/errata/RHSA-2019:1652
  vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• www.debian.org/security/2019/dsa-4431
  vendor-advisory, x_refsource_DEBIAN, NIST National Vulnerability Database
• access.redhat.com/errata/RHSA-2019:2399
  vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• lists.opensuse.org/opensuse-security-announce/2019-03/msg00040.html
  Mailing List, Third Party Advisory, vendor-advisory, x_refsource_SUSE, NIST National Vulnerability Database

Elsewhere on this site

Related CVEs (same products)

• High CVE-2026-12996 A use-after-free in OpenVPN 2.6.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows remote... Jul 30, 2026
• High CVE-2026-66035 Heap-based Buffer Overflow in Libssh2 Jul 24, 2026
• High CVE-2026-66034 Out-of-bounds Read in Libssh2 Jul 24, 2026
• High CVE-2026-66033 Out-of-bounds Read in Libssh2 Jul 24, 2026
• High CVE-2026-66032 Double Free in Libssh2 Jul 24, 2026
• Medium CVE-2026-14355 ext/openssl: Memory corruption in openssl_encrypt with AES-WRAP-PAD Jul 3, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

• No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
• No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
• No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2019-3863 is "A flaw was found in libssh2 before 1.8.1. A server could send a multiple keyboard interactive...", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 3.44% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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