CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:NCVE-2026-128121 SvelteKit: Prerendered paths are interpreted as regular expressions in Vercel route config generated by @sveltejs/adapter-vercel and @sveltejs/adapter-static
Medium (5.9). Fixed in @sveltejs/adapter-vercel 6.3.5, 7.0.2.
On this page
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to @sveltejs/adapter-vercel 6.3.5 and 7.0.2 and @sveltejs/adapter-static 3.0.11 and 4.0.1, an attacker-influenced link crawled during prerendering could be emitted into the generated Vercel routing configuration without escaping regular-expression metacharacters. The configuration could consequently interpret the path as regular-expression syntax, match unintended application paths, and expose content or behavior outside the intended path. This issue is fixed in @sveltejs/adapter-vercel 6.3.5 and 7.0.2 and @sveltejs/adapter-static 3.0.11 and 4.0.1.
Severity
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- OWASP Top 10
- A05:2025 Injection
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
- @sveltejs:adapter-static
- @sveltejs:adapter-vercel
- sveltejs:kit
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| sveltejs kit | < 2.70.4 |
| sveltejs kit | >= 3.0.0-next.0, < 3.1.1 |
| @sveltejs adapter-vercel | < 6.3.5 |
| @sveltejs adapter-vercel | >= 7.0.0-next.0, < 7.0.2 |
| @sveltejs adapter-static | < 3.0.11 |
| @sveltejs adapter-static | >= 4.0.0-next.0, < 4.0.1 |
Fix and patched versions
@sveltejs/adapter-vercel(npm): fixed in 6.3.5, 7.0.2@sveltejs/adapter-static(npm): fixed in 4.0.1, 3.0.11
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-jf9x-2fg2-hx4w | npm | @sveltejs/adapter-vercel | <6.3.5 | 6.3.5 |
| GHSA-jf9x-2fg2-hx4w | npm | @sveltejs/adapter-static | >=4.0.0-next.0 <4.0.1 | 4.0.1 |
| GHSA-jf9x-2fg2-hx4w | npm | @sveltejs/adapter-vercel | >=7.0.0-next.0 <7.0.2 | 7.0.2 |
| GHSA-jf9x-2fg2-hx4w | npm | @sveltejs/adapter-static | <3.0.11 | 3.0.11 |
Attack patterns (CAPEC)
- CAPEC-73 User-Controlled Filename Likelihood: High · Severity: High
- CAPEC-81 Web Server Logs Tampering Likelihood: Medium · Severity: High
- CAPEC-85 AJAX Footprinting Likelihood: High · Severity: Low
- CAPEC-104 Cross Zone Scripting Likelihood: Medium · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.
References
- https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac20aa5af4e2edf17e0da11dd
- https://github.com/sveltejs/kit/commit/2ed61a6aa3ac230b89e3528654c587847d1525a0
- https://github.com/sveltejs/kit/pull/17620
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-static@3.0.11
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-static@4.0.1
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-vercel@6.3.5
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-vercel@7.0.2
- https://github.com/sveltejs/kit/security/advisories/GHSA-jf9x-2fg2-hx4w