- Description
- Fiber is an Express inspired web framework written in Go. Before 2.52.11, on Go versions prior to 1.24, the underlying crypto/rand implementation can return an error if secure randomness cannot be obtained. Because no error is returned by the Fiber v2 UUID functions, application code may unknowingly rely on predictable, repeated, or low-entropy identifiers in security-critical pathways. This is especially impactful because many Fiber v2 middleware components (session middleware, CSRF, rate limiting, request-ID generation, etc.) default to using utils.UUIDv4(). This vulnerability is fixed in 2.52.11.
- Source
- security-advisories@github.com
- NVD status
- Analyzed
- Products
- fiber
CVSS 4.0
- Type
- Secondary
- Base score
- 9.2
- Impact score
- -
- Exploitability score
- -
- Vector string
- CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/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
- Severity
- CRITICAL
CVSS 3.1
- Type
- Primary
- Base score
- 9.4
- Impact score
- 5.5
- Exploitability score
- 3.9
- Vector string
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
- Severity
- CRITICAL
- security-advisories@github.com
- CWE-338
- Hype score
- Not currently trending
The `Fiber` web framework (CVE-2025-66630) may generate predictable UUIDs if `crypto/rand` fails. This could impact application security if UUIDs are used for sensitive identifiers. Update to `2.52.11`. #Go #WebFramework #Security https://t.co/03ufNIAYDS
@pulsepatchio
11 Feb 2026
33 Impressions
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CVE-2025-66630 Fiber is an Express inspired web framework written in Go. Before 2.52.11, on Go versions prior to 1.24, the underlying crypto/rand implementation can return an error … https://t.co/CjAW7mi4Ui
@CVEnew
9 Feb 2026
174 Impressions
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CVE-2025-66630: The Null Identity: Unmasking Fiber's Critical 'Zero-UUID' Vulnerability A critical failure in the Fiber web framework's random number generation logic allows for the creation of predictable, zero-value UUIDs. This flaw leads to catastr... https://t.co/vQDdafLVM4
@_cvereports
9 Feb 2026
33 Impressions
0 Retweets
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