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Improper input validation in removing style tag in libsubextractor.so prior to SMR Sep-2026 Release 1 allows local attackers to write out-of-bounds… (CVE-2026-21089)

0
Medium
Published: 09/09/2026 (09/09/2026, 06:31:38 UTC)
Source: GCVE Database

Description

CVE-2026-21089 is a vulnerability in libsubextractor.so prior to SMR Sep-2026 Release 1 where improper input validation during the removal of style tags allows local attackers to write out-of-bounds memory. This flaw could lead to memory corruption. The vulnerability has a medium severity rating. No known exploits are reported in the wild. No patch or remediation details are currently provided.

CVSS v4.0

Attack Vector
Local
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
Passive
Vuln. Confidentiality
Low
Vuln. Integrity
High
Vuln. Availability
Low
Subsq. Confidentiality
None
Subsq. Integrity
None
Subsq. Availability
None
Scope
X
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/09/2026, 13:58:08 UTC

Technical Analysis

This vulnerability involves improper input validation in the process of removing style tags within the libsubextractor.so component before SMR Sep-2026 Release 1. The flaw permits local attackers to perform out-of-bounds memory writes, potentially causing memory corruption or instability. The CVSS 4.0 vector indicates local attack vector with low complexity and no privileges required, but user interaction is needed. The overall impact is moderate, with no known active exploitation or vendor patch information available at this time.

Potential Impact

Local attackers can exploit this vulnerability to write out-of-bounds memory, which may lead to memory corruption and potentially affect the stability or security of the affected system. There are no reports of active exploitation in the wild.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or patch links are provided, users should monitor vendor communications for updates and avoid untrusted local code execution until a fix is available.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-fv7f-g3wg-p3v5
Osv Schema Version
1.4.0
Aliases
["CVE-2026-21089"]
Ecosystems
[]
Database Specific Severity
MODERATE
Cvss Version
4.0

Threat ID: 6aa15f7cacd9273b49618396

Added to database: 09/09/2026, 13:30:36 UTC

Last enriched: 09/09/2026, 13:58:08 UTC

Last updated: 09/09/2026, 19:52:22 UTC

Views: 3

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