Raw vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/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:XSummary
CVE-2025-9146 is a high-severity Use of a Broken or Risky Cryptographic Algorithm (CWE-327) vulnerability in Linksys E5600 Firmware. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Adversary-in-the-Middle (T1557); ranked at the 42th 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 SC-13 (Cryptographic Protection) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-9146 is a vulnerability in the Linksys E5600 router running firmware version 1.1.0.26. The flaw resides in the verify_gemtek_header function within the checkFw.sh script of the Firmware Handler component. It enables the use of a risky cryptographic algorithm, classified under CWE-310 (Cryptographic Issues) and CWE-327 (Use of a Broken or Risky Cryptographic Algorithm). The issue carries a CVSS v3.1 base score of 6.6 (AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H) and was published on 2025-08-19.
The vulnerability can be exploited remotely by attackers who possess high privileges (PR:H) on the target system, though it demands high attack complexity (AC:H) and is described as difficult to exploit. Successful exploitation grants high impacts across confidentiality, integrity, and availability (C:H/I:H/A:H), potentially allowing full compromise of the device's firmware handling process, such as improper validation during updates.
Advisories from VulDB detail the issue but note that the vendor was contacted early without any response. No patches or official mitigations are available from Linksys, as referenced on their site and in the VulDB entries. Additional technical analysis appears in a GitHub repository documenting IoT firmware updates for the Linksys E5600.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-28817
Vulnerability Data
A flaw has been found in Linksys E5600 1.1.0.26. The affected element is the function verify_gemtek_header of the file checkFw.sh of the component Firmware Handler. Executing manipulation can lead to risky cryptographic algorithm. The attack may be launched remotely. The…
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attack requires a high level of complexity. The exploitability is described as difficult. The vendor was contacted early about this disclosure but did not respond in any way.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 6 hardening rules · 6 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
SC-13 requires selection and implementation of specific cryptography types, directly stopping use of broken algorithms.
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.
PR.DS-01 promotes encryption for data-at-rest but never requires strong algorithms, leaving CWE-327 fully possible; the weakness is also far broader than data-at-rest so one narrow control removes none of its total risk.
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.
Mandating approved algorithms, cipher strength and usage standards directly stops the selection of broken or weak cryptographic primitives that attackers can exploit.
The explicit call-out of cryptography-related legal constraints (import/export, key escrow, digital-signature validity) reduces the likelihood that an organization will adopt broken or non-compliant cryptographic algorithms that violate those rules.
Access to current specialist guidance and early vulnerability alerts enables timely replacement of broken or risky cryptographic algorithms with stronger alternatives.
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` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248524 OL 8 must implement NIST FIPS-validated cryptography for the following: To provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-327
Windows 10 (1 rule)
- V-220937 The system must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows 11 (1 rule)
- V-253461 The system must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows Server 2016 (1 rule)
- V-225053 Windows Server 2016 must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows Server 2019 (1 rule)
- V-205654 Windows Server 2019 must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows Server 2022 (1 rule)
- V-254474 Windows Server 2022 must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327