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CVE-2017-11519: TP Link Archer C9 (2.0) Firmware: Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG)

CVE-2017-11519 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists TP Link Archer C9 (2.0) Firmware as the affected product. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

passwd_recovery.lua on the TP-Link Archer C9(UN)_V2_160517 allows an attacker to reset the admin password by leveraging a predictable random number generator seed. This is fixed in C9(UN)_V2_170511.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-335: Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG)

The product uses a Pseudo-Random Number Generator (PRNG) but does not correctly manage seeds.

Affected products

  • TP Link Archer C9 (2.0) Firmware: 160517

References