Weakness · High

CWE-208: Observable Timing Discrepancy

What it is

Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.

MITRE CWE 4.19.1

Severity (our rating)
High
Likelihood of exploit
Not rated by MITRE
Introduced during
Architecture and Design, Implementation, Operation
Exploited in the wild
No CVE in CISA's catalog

In more detail

In security-relevant contexts, even small variations in timing can be exploited by attackers to indirectly infer certain details about the product's internal operations. For example, in some cryptographic algorithms, attackers can use timing differences to infer certain properties about a private key, making the key easier to guess. Timing discrepancies effectively form a timing side channel.

What an attacker can do

  • Read Application Data (Confidentiality, Access Control)
  • Bypass Protection Mechanism (Confidentiality, Access Control)

How to prevent it

MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.

CWE-208 on MITRE's CWE site

H2 Security

Found it in your code?

We review where it appears, fix it with your team, and check it was not already used against you.

Talk to our team

T Academy

Stop writing it in the first place

Learn to build software and systems without weaknesses like this one, with practice on real hosts in your browser, every objective checked on the machine.

Start free

Source: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.