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TI-2021-09320 Aliases CVE-2021-28040GHSA-87rm-8q5w-499g

An issue was discovered in OSSEC 3.6.0.

Priority LOW 35CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-674.

Summary

An issue was discovered in OSSEC 3.6.0. An uncontrolled recursion vulnerability in os_xml.c occurs when a large number of opening and closing XML tags is used. Because recursion is used in _ReadElem without restriction, an attacker can trigger a segmentation fault once unmapped memory is reached.

Why it matters now

EPSS 0.01192 68th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ossec:ossec:3.6.0:*:*:*:*:*:*:*3.6.0VulnerableOSSEC
  • cpe:2.3:a:ossec:ossec:3.6.0:*:*:*:*:*:*:* Versions 3.6.0 Vulnerable ·OSSEC

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-28040
  2. 2026-10-03 Alias added: GHSA-87rm-8q5w-499g

References

Exploit 1

  • TI-2020-06781 In OSSEC-HIDS 2.7 through 3.5.0, the server component responsible for log analysis… CVSS 3.1CRITICAL 9.8
  • TI-2020-06780 In OSSEC-HIDS 2.7 through 3.5.0, the server component responsible for log analysis… CVSS 3.1CRITICAL 9.8
  • TI-2020-06784 In OSSEC-HIDS 2.7 through 3.5.0, the server component responsible for log analysis… CVSS 3.1CRITICAL 9.8
  • TI-2020-06782 In OSSEC-HIDS 2.7 through 3.5.0, the OS_CleanMSG function in ossec-analysisd doesn't… CVSS 3.1CRITICAL 9.8
  • TI-2020-06779 In OSSEC-HIDS 2.7 through 3.5.0, the server component responsible for log analysis… CVSS 3.1HIGH 8.8
  • TI-2014-04316 host-deny.sh in OSSEC before 2.8.1 writes to temporary files with predictable filenames… CVSS 2.0HIGH 7.2
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences