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Improper input validation in loading a subtitle frame in libsubextractor.so prior to SMR Sep-2026 Release 1 allows local attackers to write… (CVE-2026-21088)

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

Description

CVE-2026-21088 is a vulnerability in libsubextractor.so prior to SMR Sep-2026 Release 1 where improper input validation when loading a subtitle frame allows local attackers to write out-of-bounds memory. This flaw could lead to memory corruption. No known exploits are reported in the wild. The severity is assessed as medium based on available data.

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, 13:57:29 UTC

Technical Analysis

This vulnerability involves improper input validation in the subtitle frame loading functionality of libsubextractor.so before SMR Sep-2026 Release 1. Local attackers can exploit this flaw to write outside the intended memory bounds, potentially causing memory corruption. The vulnerability does not have a CVSS score but is rated as moderate in the GCVE database. There is no information about a patch or fix availability in the provided data.

Potential Impact

Successful exploitation allows local attackers to write out-of-bounds memory, which may lead to memory corruption and potentially affect the stability or security of the affected system. No further impact details or exploitation in the wild are reported.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround information is provided in the available data.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-rvhf-9rr9-xw9h
Osv Schema Version
1.4.0
Aliases
["CVE-2026-21088"]
Ecosystems
[]
Database Specific Severity
MODERATE
Cvss Version
4.0

Threat ID: 6aa15f7bacd9273b49618376

Added to database: 09/09/2026, 13:30:35 UTC

Last enriched: 09/09/2026, 13:57:29 UTC

Last updated: 09/09/2026, 20:12:19 UTC

Views: 2

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