Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2024-20378 is a high-severity Authentication Bypass by Primary Weakness (CWE-305) vulnerability in Cisco Ip Phone 6821 With Multiplatform Firmware. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Junk Data (T1001.001); ranked in the top 44% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to IA-2 (Identification and Authentication (Organizational Users)) and IA-8 (Identification and Authentication (Non-organizational Users)) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2024-18093
Vulnerability Data
A vulnerability in the web-based management interface of Cisco IP Phone firmware could allow an unauthenticated, remote attacker to retrieve sensitive information from an affected device. This vulnerability is due to a lack of authentication for specific endpoints of the…
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web-based management interface on an affected device. An attacker could exploit this vulnerability by connecting to the affected device. A successful exploit could allow the attacker to gain unauthorized access to the device, enabling the recording of user credentials and traffic to and from the affected device, including VoIP calls that could be replayed.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 5 hardening rules · 3 OS baselines
V6.4.3
Mitigating Controls (NIST 800-53 r5) AI
Requires unique identification and authentication of users, structurally blocking bypass of the mechanism.
Requires unique identification and authentication of non-organizational users, blocking bypass paths.
Enforces approved authorizations so a bypass weakness cannot be exploited to reach resources.
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.
Identifying and recording vulnerabilities catches the primary weaknesses that allow authentication bypass.
Strong authentication mechanisms and policy enforcement directly reduce bypass opportunities arising from implementation flaws.
Secure development practices throughout the SDLC prevent the primary weaknesses that enable authentication bypass.
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.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).
Ubuntu 22.04 (1 rule)
- V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. blocks CWE-305
Ubuntu 24.04 (1 rule)
- V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. blocks CWE-305