CVE-2025-54801
Fiber Susceptible to Crash via `BodyParser` Due to Unvalidated Large Slice Index in Decoder
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Fiber is an Express inspired web framework written in Go. In versions 2.52.8 and below, when using Fiber's Ctx.BodyParser to parse form data containing a large numeric key that represents a slice index (e.g., test.18446744073704), the application crashes due to an out-of-bounds slice allocation in the underlying schema decoder. The root cause is that the decoder attempts to allocate a slice of length idx + 1 without validating whether the index is within a safe or reasonable range. If the idx is excessively large, this leads to an integer overflow or memory exhaustion, causing a panic or crash. This is fixed in version 2.52.9.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| NVDNVD · Analyzed | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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 |
- EPSS (exploitation in 30 days)
- 0.42% · top 63% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/gofiber/fiber/v2GHSA-qx2q-88mx-vhg7 (opens in a new tab)
References (2)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-qx2q-88mx-vhg7 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2025-54801)Record last updated .