Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
GoFiber's helmet middleware in github.com/gofiber/fiber versions before 3.4.0 never sets the Strict-Transport-Security header, even when HSTSMaxAge is configured, because it checks the HTTP protocol version instead of the URL scheme. An attacker positioned on the network path, such as on public Wi-Fi, can perform SSL stripping and downgrade HTTPS connections to HTTP. Upgrade to github.com/gofiber/fiber 3.4.0 or later.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 4.8 | Medium | 3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0021, the 11th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 2 Jul 2026, 07:57 UTC Published by the maintainers as a GitHub repository advisory
- 31 Oct 2026, 14:56 UTC First seen by agentprime
- 31 Oct 2026, 14:56 UTC Confirmed by OSV