CVE-2026-109854

Description

A flaw was found in m17n-lib. An attacker who supplies crafted input to an application processing ISO-2022 encoded text can cause the library to read uninitialized memory from the stack. If the application exposes or returns the decoded output, this flaw can result in unexpected behavior and limited information disclosure.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score2.5N/A2.5
Attack VectorLocalN/ALocal
Attack ComplexityHighN/AHigh
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ARequired
ScopeUnchangedN/AUnchanged
ConfidentialityLowN/ALow
Integrity ImpactNoneN/ANone
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

cve.org: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Understanding the Weakness (CWE)

Availability,Integrity,Other

Technical Impact: Other

Initial variables usually contain junk, which can not be trusted for consistency. This can lead to denial of service conditions, or modify control flow in unexpected ways. In some cases, an attacker can "pre-initialize" the variable using previous actions, which might enable code execution. This can cause a race condition if a lock variable check passes when it should not.

Authorization,Other

Technical Impact: Other

Strings that are not initialized are especially dangerous, since many functions expect a null at the end -- and only at the end -- of a string.

Acknowledgements

Red Hat would like to thank Chamod Anuradha Denipitiya for reporting this issue.

Frequently Asked Questions

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