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  4. CVE 2026 58051 libssh2 free of uninitialized pointer in
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Back to active CVEs
High · CVSS 8.3CVE-2026-58051

libssh2 - Free of Uninitialized Pointer in publickey List CleanupCVE-2026-58051

Answer in brief

CVE-2026-58051 records a High severity (CVSS 8.3) vulnerability in libssh2 - Free of Uninitialized Pointer in publickey List Cleanup. The current sources do not mark it as known exploited. The current feed maps libssh2/libssh2 (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jun 28, 2026Updated Nov 10, 2026Source checked Nov 10, 2026First seen by HOL Jun 28, 2026Material review Nov 10, 2026
Upstream Advisory

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
CWE-908
Source
CVE List V5
Source checked
Nov 10, 2026
References
4 linked sources
Open source record

Key facts

Risk
High · CVSS 8.3
Exploitation
Not marked as known exploited
Affected software
7 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 8.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps libssh2/libssh2 (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:a:libssh2:libssh2:*:*:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
libssh2/libssh2generic*Not reported
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)generic>=V3.1.7 <**
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)generic>=V3.1.7 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)generic>=V3.1.7 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)generic>=V3.1.7 <**
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)generic>=V3.1.7 <**

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for libssh2/libssh2, Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0).
  2. 2Review the reported fix. Update Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) to *; Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) to *; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) to * if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Jun 28, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Nov 10, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Jun 28, 2026

Sources and claim methodology

  • Source referencecert-portal.siemens.com
  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
  • Source referencevulncheck.com
Upstream source description

libssh2 through 1.11.1 grows its publickey list with SSH2_REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2_publickey_list_free operating on an uninitialized entry. A malicious SSH server offering the publickey subsystem can use a malformed response to make cleanup free an uninitialized, attacker-influenceable attrs pointer in a connecting libssh2 client.

Quoted source text, attributed separately from HOL analysis.