Cyber Resilience

CVE-2025-9828

LowPublic PoC

Published: 02 September 2025

Published
02 September 2025
Modified
29 April 2026
KEV Added
Patch
CVSS Score v4 2.9 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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:X
EPSS Score 0.0013 33.0th percentile
Risk Priority 6 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-9828 is a low-severity Use of a Broken or Risky Cryptographic Algorithm (CWE-327) vulnerability in Tenda Cp6 Firmware. Its CVSS base score is 2.9 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Weaken Encryption (T1600); ranked at the 33.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

A vulnerability was determined in Tenda CP6 11.10.00.243. The affected element is the function sub_2B7D04 of the component uhttp. Executing manipulation can lead to risky cryptographic algorithm. The attack may be launched remotely. This attack is characterized by high complexity.…

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The exploitability is described as difficult. The exploit has been publicly disclosed and may be utilized.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1600 Weaken Encryption Defense Impairment
Adversaries may compromise a network device’s encryption capability in order to bypass encryption that would otherwise protect data communications.
Why these techniques?

The vulnerability (CWE-327) uses a risky cryptographic algorithm (additive checksum) in the uhttp component's sub_2B7D04 function for firmware update integrity verification, allowing remote attackers to craft and upload malicious firmware for arbitrary code execution or DoS by bypassing validation; explicitly mapped to T1600 Weaken Encryption by VulDB.

Affected Assets

tenda
cp6 firmware
11.10.00.243

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-327

Contacts with security groups provide timely information on broken or risky cryptographic algorithms, reducing the likelihood of their selection and use.

addresses: CWE-327

Ongoing education and sharing of recommended practices helps organizations identify and migrate away from broken or risky cryptographic algorithms.

addresses: CWE-327

Cross-organization threat feeds commonly include advances in cryptanalysis and active exploits against weak or broken algorithms, allowing organizations to deprecate them proactively.

addresses: CWE-327

Capital planning and funding allow selection and ongoing support of strong cryptographic algorithms rather than weak or broken ones.

addresses: CWE-327

Risk updates surface newly-broken or risky cryptographic algorithms as threat intelligence and computing advances evolve, enabling timely replacement.

addresses: CWE-327

Scanners flag use of broken or weak cryptographic algorithms via known-vulnerability databases.

addresses: CWE-327

Enforces approved cryptographic algorithms for each use case, blocking use of broken or risky algorithms.

addresses: CWE-327

Flaw remediation replaces broken or risky cryptographic algorithms once safer implementations are released by vendors.

References