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Insecurely generated token - OTP

Description

The OTP is generated client-side and sent to the server, so an attacker only needs to intercept the request to access the token and continue the application flow without needing access to the phone number used.

Impact

Make requests without having access to the telephone number used or even use a fake telephone number.

Recommendation

Generate OTPs and perform the corresponding validations always on the server side.

Threat

Anonymous attacker from the Internet.

Expected Remediation Time

⌚ 60 minutes.

Score

Default score using CVSS 3.1. It may change depending on the context of the src.

Base

  • Attack vector: N
  • Attack complexity: L
  • Privileges required: N
  • User interaction: N
  • Scope: U
  • Confidentiality: N
  • Integrity: L
  • Availability: N

Temporal

  • Exploit code madurity: X
  • Remediation level: X
  • Report confidence: X

Result

  • Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:X/RL:X/RC:X
  • Score:
    • Base: 5.3
    • Temporal: 5.3
  • Severity:
    • Base: Medium
    • Temporal: Medium

Score 4.0

Default score using CVSS 4.0 . It may change depending on the context of the src.

Base 4.0

  • Attack vector: N
  • Attack complexity: L
  • Attack Requirements: N
  • Privileges required: N
  • User interaction: N
  • Confidentiality (VC): N
  • Integrity (VI): L
  • Availability (VA): N
  • Confidentiality (SC): N
  • Integrity (SI): N
  • Availability (SA): N

Threat 4.0

  • Exploit madurity: X

Result 4.0

  • Vector string: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X
  • Score:
    • CVSS-BT: 6.9
  • Severity:
    • CVSS-BT: Medium

Requirements

Fixes

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