EUVD-2026-110622
GHSA-v47w-qwhq-fc6f
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessSupply crafted text to a Qt application
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ExploitApp converts input to TSCII via QTextCodec
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ExecutionOut-of-bounds read past input buffer in codec
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ImpactApplication crash or data misinterpretation
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Bounds checking, read limits
MITRE ATT&CK
1 technique across 1 tactic: Collection The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires an application that (1) links the Qt 5 Compatibility APIs module (qt5compat / QTextCodec, legacy Qt Core in Qt 5 and earlier) and (2) actually converts attacker-influenced text to the TSCII encoding (Tamil Script Code for Information Interchange) through QTextCodec. TSCII is a rarely-used legacy encoding, so the vast majority of Qt applications never reach this code path, sharply limiting real exposure. Limiting factors confirmed by CVSS 4.0: local vector (AV:L) and required passive user interaction (UI:P) - the app must process the attacker-supplied input - and the impact is confined to availability (VA:H, crash) or data misinterpretation, with no confidentiality or integrity compromise (VC:N/VI:N). |
| Impact | This is a medium-severity (CVSS 4.0 base 4.3), low-priority issue in practice. The CVSS 4.0 vector is local (AV:L), low complexity (AC:L), requires no privileges (PR:N) but passive user interaction (UI:P), and produces only an availability impact (VA:H) with no confidentiality or integrity impact (VC:N/VI:N) - i.e. a crash or data misinterpretation, not memory disclosure to the attacker. EPSS is 0.12% (2nd percentile), it is NOT listed in CISA KEV, and no public exploit is referenced, so exploitation status is 'no public exploit identified at time of analysis.' All signals align toward low real-world risk: a hard-to-reach denial-of-service in a legacy encoding path rather than a priority threat. CONFLICT TO NOTE: the input 'Information Disclosure' tag contradicts the CVSS 4.0 metrics (VC:N) and the description, which describe a crash or data misinterpretation - not confidentiality disclosure; treat this as an availability/DoS bug, not an info-leak. The vuln.today decision label is 'this_month,' consistent with a routine-cycle patch rather than an emergency. |
| Exploit ScenarioDerived | An application built on Qt that links the Qt 5 Compatibility APIs (qt5compat) module and converts attacker-influenced text to the TSCII encoding via QTextCodec is fed a crafted input string; the TSCII codec reads past the end of the input buffer, crashing the application or causing it to misinterpret the data. Exploitation is local and requires the app to actually process the attacker-supplied data through the vulnerable TSCII path (UI:P). No public exploit code is referenced. |
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Alert meAnalysisAIv1 – Oct 28, 2026
An out-of-bounds read in Qt's qt5compat QTextCodec TSCII encoder can crash an application or cause it to return misinterpreted text when it converts attacker-influenced input to the legacy TSCII encoding. The issue is rated CVSS 4.0 4.3 (medium) and is constrained by a local attack vector (AV:L) plus required user interaction (UI:P); exploitation needs an application that links the Qt 5 Compatibility APIs and actually performs TSCII conversion, a rare code path. EPSS is 0.12% (2nd percentile), no public exploit was identified at time of analysis, and a vendor patch is available.
RemediationAI
Patch available per vendor advisory: Qt has published a fix reference in its known-vulnerabilities advisory and a qt5compat code review, but the supplied data does not specify an exact fixed release version, so confirm the patched qt5compat/Qt version with the vendor before upgrading. Until then, avoid converting untrusted or attacker-influenced text to TSCII through QTextCodec; applications that do not need TSCII should not register or use that codec for such input, with the trade-off that legitimate Tamil TSCII text will not be processed. Because exploitation requires the application to reach the TSCII conversion path and the impact is limited to crashes or misinterpreted output, prioritize this month per the vuln.today decision and validate the vendor advisory links: https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-107472 and https://codereview.qt-project.org/c/qt/qt5compat/+/762021.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The flaw is CWE-125 (out-of-bounds read) in the TSCII (Tamil Script Code for Information Interchange) encoder exposed through QTextCodec in Qt's Qt 5 Compatibility APIs module, qt5compat, with related legacy Qt Core code in Qt 5 and earlier. When an application asks QTextCodec to convert text into TSCII, the encoder may read beyond the bounds of the input buffer; the supplied sources do not describe the precise trigger condition beyond that conversion path. The CPE cpe:2.3:a:qt:qt:*:*:*:*:*:*:*:* identifies Qt as the affected product, and EUVD lists Qt 4.0.0 through 6.8.8 and Qt 6.9.0 through 6.11.2 as affected ranges. Impact is confined to availability (crash) or data misinterpretation; the independent CVSS 3.1 vector is AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H, and the CVSS 4.0 vector is AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H, so confidentiality and integrity are not affected. Because TSCII is a rarely used legacy encoding, most Qt applications never execute this conversion path.
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Severity by source
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/R:U/RE:L/U:Green
Attacker-supplied text must be processed locally through the app's TSCII codec (AV:L, UI:R); the out-of-bounds read only crashes or corrupts output, so C:N/I:N/A:H.
Primary rating from Vendor (Qt).
CVSS VectorVendor: Qt
DescriptionCVE.org
An out-of-bounds read vulnerability in the QTextCodec TSCII encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Applications that convert text to the TSCII encoding through QTextCodec may read memory outside the input buffer, which can cause the application to crash or misinterpret the data.
Threat Intelligence Overview
NVD
CVE.org
EPSS
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
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Exploit-DB