CWE-208: Observable Timing Discrepancy

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.

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.

Consequences

• Confidentiality, Access Control: Read Application Data, Bypass Protection Mechanism

Recent advisories

• EEF-CVE-2026-65630 — Timing side-channel in pure-Erlang X25519 scalar multiplication leaks the private key in jose
• GHSA-34fc-gh42-pj53 — OpenBao's Recovery Mode Vulnerable To Token Leakage via Timing Attack
• GO-2026-6558 — Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle
• GHSA-38p6-h87p-r4cg — Grav: Non constant time nonce comparison in Utils::verifyNonce() used for CSRF protection
• GHSA-g6cj-pr64-35w5 — cryptography: PKCS#7 EnvelopedData decryption exposes a Bleichenbacher oracle through distinguishable errors and timing
• GHSA-7rw5-9f7q-xj36 — Open WebUI: Account enumeration via observable login timing discrepancy
• GHSA-jr54-jwhj-55gp — NocoDB: User Enumeration via Sign-In Timing
• GHSA-7w52-7jvm-m9vw — Shopware: Timing-attack on admin panel allowing enumeration of administrator usernames
• GHSA-9m89-8frq-c98c — Apache Tomcat - AJP secret compared in non-constant time
• GHSA-6x2q-h3cr-8j2h — Traefik: A timing side-channel vulnerability allows for valid username enumeration via BasicAuth middleware
• GHSA-vxf7-qj7q-83fh — Spring Security Vulnerable to User Attribute Enumeration when Using DaoAuthenticationProvider
• GHSA-jrc6-fmhw-fpq2 — Kimai: Username enumeration via timing on X-AUTH-USER
• GHSA-mj7r-x3h3-7rmr — ApostropheCMS: User Enumeration via Timing Side Channel in Password Reset Endpoint
• GHSA-mmpq-5hcv-hf2v — Parse Server has a login timing side-channel reveals user existence
• GHSA-jj6q-rrrf-h66h — OpenClaw: Shared-secret comparison call sites leaked length information through timing

All advisories for CWE-208