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Back to active CVEs
High · CVSS 7.8CVE-2021-3999

CVE Program ContainerCVE-2021-3999

Answer in brief

CVE-2021-3999 records a High severity (CVSS 7.8) vulnerability in CVE Program Container. The current sources do not mark it as known exploited. The current feed maps n/a/glibc (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic), Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

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

Published Aug 24, 2022Updated Oct 14, 2026Source checked Oct 14, 2026First seen by HOL Oct 14, 2026Material review Oct 14, 2026
Upstream Advisory

Key facts

Risk
High · CVSS 7.8
Exploitation
Not marked as known exploited
Affected software
4 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 7.8. 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 n/a/glibc (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (generic), Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
n/a/glibcgenericFixed in glibc v2.31 and above.Not reported
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.0 <V3.1.5V3.1.5
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric>=V3.1.0 <V3.1.5V3.1.5
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.0 <V3.1.5V3.1.5

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for n/a/glibc, Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP.
  2. 2Review the reported fix. Update Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to V3.1.5; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Aug 24, 2022

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

  2. Source modified

    Oct 14, 2026

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

  3. First seen by HOL

    Oct 14, 2026

Sources and claim methodology

  • Source referenceaccess.redhat.com
  • Source referencebugzilla.redhat.com
  • Source referencecert-portal.siemens.com
  • Source referencecert-portal.siemens.com
  • Source referencelists.debian.org
  • Source referencesecurity.netapp.com
  • Source referencesecurity-tracker.debian.org
  • Source referencesourceware.org
  • Source referencesourceware.org
  • Source referenceopenwall.com
Upstream source description

A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system.

Quoted source text, attributed separately from HOL analysis.

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  • WPCode 2.0.0 - 2.3.9 - Unauthenticated Snippet Suppression via Safe Mode BypassSame generic ecosystem
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  • Stack overwrite from a specially crafted and formatted SVCB or HTTPS RRSame generic ecosystem

Record context

Vulnerability class
Memory Corruption
EPSS
Not reported
CWE IDs
CWE-193
Source
CVE List V5
Source checked
Oct 14, 2026
References
10 linked sources
Open source record