CVE-2026-105294
Raw vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/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:XCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-105294 is a critical-severity External Control of System or Configuration Setting (CWE-15) vulnerability. Its CVSS base score is 9.1 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Winlogon Helper DLL (T1547.004); ranked at the 8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-92158
Vulnerability Data
Legcord 1.1.0 through 1.3.0 contains a configuration injection vulnerability that allows script in the Discord page to write any config key via the window.legcord settings.setConfig bridge. Attackers exploiting a Discord XSS can set additionalArguments to persistently add --proxy-server and --ignore-certificate-errors…
more
switches, routing all client traffic through an interception proxy.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 4 hardening rules · 2 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Enforces approved authorizations for logical access to configuration resources so external parties cannot alter them.
Limits privileges to the minimum needed, reducing the set of users who can externally modify configuration.
Enforces documented access restrictions on all changes to system configuration, directly blocking unauthorized external control of settings.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Formal change and exception management catches externally driven configuration alterations.
Least-privilege access policies reduce unauthorized external modification of configuration values.
Hardened configuration baselines and change controls directly limit external manipulation of settings.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
A.5.15 only requires that access control policies and rules be defined and documented; it does not itself enforce, implement or configure those rules to stop external control of system/configuration settings, so the weakness remains fully exploitable.
A.5.18 governs the provisioning, review, and revocation of authorized access rights; it has no bearing on whether a system or configuration setting can be externally controlled by a user (CWE-15).
Documented operating procedures define how configuration changes must be performed.
Use of privileged utility programs is controlled to prevent misuse of configuration tools.
Privileged access rights reduce the number of users who can alter configuration.