CVE-2024-53261
Cross-Site Scripting attack (XSS) on dev mode 404 page in SvelteKit
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. "Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)." The files packages/kit/src/exports/vite/dev/index.js and packages/kit/src/exports/vite/utils.js both contain user controllable data which under specific conditions may flow to dev mode pages. There is little to no expected impact. The Vite development is not exposed to the network by default and even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data. None the less this issue has been addressed in version 2.8.3 and all users are advised to upgrade.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Active
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cross-Site Scripting attack (XSS) on dev mode 404 page in SvelteKit
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. "Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)." The files packages/kit/src/exports/vite/dev/index.js and packages/kit/src/exports/vite/utils.js both contain user controllable data which under specific conditions may flow to dev mode pages. There is little to no expected impact. The Vite development is not exposed to the network by default and even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data. None the less this issue has been addressed in version 2.8.3 and all users are advised to upgrade.
- Record
CVE-2024-53261- CVSS 4.0
- 2.0 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2024-3380
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. "Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)." The files packages/kit/src/exports/vite/dev/index.js and packages/kit/src/exports/vite/utils.js both contain user controllable data which under specific conditions may flow to dev mode pages. There is little to no expected impact. The Vite development is not exposed to the network by default and even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data. None the less this issue has been addressed in version 2.8.3 and all users are advised to upgrade.
- Record
EUVD-2024-3380- CVSS 4.0
- 2.0 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-rjjv-87mx-6x3h
@sveltejs/kit vulnerable to XSS on dev mode 404 page
Summary
"Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)."
Details
Source of potentially tainted data is in packages/kit/src/exports/vite/dev/index.js, line 437. This potentially tainted data is passed through a number of steps (which I could detail if you'd like) all the way down to line 91 in packages/kit/src/exports/vite/utils.js, which performs an operation that Snyk believes an attacker shouldn't be allowed to manipulate.
Another source of potentially tainted data (according to Snyk) comes from packages/kit/src/exports/vite/utils.js, line 30, col 30 (i.e., the url property of req). This potentially tainted data is passed through a number of steps (which I could detail if you'd like) all the way down line 91 in packages/kit/src/exports/vite/utils.js, which performs an operation that Snyk believes an attacker shouldn't be allowed to manipulate.
PoC
Not provided
Impact
Little to none. The Vite development is not exposed to the network by default. And even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data.
- Record
GHSA-rjjv-87mx-6x3h- CVSS 3.1
- 0.0 None
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. "Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)." The files packages/kit/src/exports/vite/dev/index.js and packages/kit/src/exports/vite/utils.js both contain user controllable data which under specific conditions may flow to dev mode pages. There is little to no expected impact. The Vite development is not exposed to the network by default and even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data. None the less this issue has been addressed in version 2.8.3 and all users are advised to upgrade.
- Record
CVE-2024-53261- CVSS 4.0
- 2.0 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/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 - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
Cross-Site Scripting attack (XSS) on dev mode 404 page in SvelteKit
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. "Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)." The files packages/kit/src/exports/vite/dev/index.js and packages/kit/src/exports/vite/utils.js both contain user controllable data which under specific conditions may flow to dev mode pages. There is little to no expected impact. The Vite development is not exposed to the network by default and even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data. None the less this issue has been addressed in version 2.8.3 and all users are advised to upgrade.
- Record
CVE-2024-53261- CVSS 4.0
- 2.0 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVGHSA-rjjv-87mx-6x3h
@sveltejs/kit vulnerable to XSS on dev mode 404 page
Summary
"Unsanitized input from the request URL flows into end, where it is used to render an HTML page returned to the user. This may result in a Cross-Site Scripting attack (XSS)."
Details
Source of potentially tainted data is in packages/kit/src/exports/vite/dev/index.js, line 437. This potentially tainted data is passed through a number of steps (which I could detail if you'd like) all the way down to line 91 in packages/kit/src/exports/vite/utils.js, which performs an operation that Snyk believes an attacker shouldn't be allowed to manipulate.
Another source of potentially tainted data (according to Snyk) comes from packages/kit/src/exports/vite/utils.js, line 30, col 30 (i.e., the url property of req). This potentially tainted data is passed through a number of steps (which I could detail if you'd like) all the way down line 91 in packages/kit/src/exports/vite/utils.js, which performs an operation that Snyk believes an attacker shouldn't be allowed to manipulate.
PoC
Not provided
Impact
Little to none. The Vite development is not exposed to the network by default. And even if someone were able to trick a developer into executing an XSS against themselves, a development database should not have any sensitive data.
- Record
GHSA-rjjv-87mx-6x3h- CVSS 3.1
- 0.0 None
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@sveltejs/kitnpm |
before 2.8.3 | 2.8.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-53261 is a low vulnerability (CVSS 2.0) in Svelte Sveltekit, published November 25, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 28th percentile. Fixed in @sveltejs/kit 2.8.3.
References
github.com/sveltejs/kit/security/advisories/GHSA-rjjv-87mx-6x3h
nvd.nist.gov/vuln/detail/CVE-2024-53261