Svelte
CVE-2026-22803
HIGH
GHSA-j2f3-wq62-6q46
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessCraft malicious binary payload
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DeliverySubmit via form remote function
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ExploitTrigger excessive memory allocation
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ExecutionExhaust server memory
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ImpactService becomes unavailable
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Memory allocation limits
|
| Exploitation Conditions | SvelteKit versions 2.49.0 to 2.49.4 with experimental form remote function enabled. No authentication required; remote unauthenticated exploitation possible against default configurations accepting form submissions. |
| Impact | CVSS 7.5 (HIGH). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: None. Exploitable via remote/network. |
| Exploit ScenarioDerived | A remote attacker could exploit this vulnerability to compromise the affected system. |
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Alert meAnalysisAIv1 – Mar 12, 2026
SvelteKit versions 2.49.0 through 2.49.4 are vulnerable to denial-of-service attacks through the experimental form remote function, which fails to properly validate binary-encoded form payloads and can be exploited to exhaust server memory. An unauthenticated remote attacker can craft a malicious payload to trigger excessive memory allocation, rendering affected applications unavailable. The vulnerability is resolved in version 2.49.5.
Earlier versions of this analysis (1)
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. [CVSS 7.5 HIGH]
RemediationAI
A vendor patch is available — apply it immediately. Fixed in version 2.49.5.. Restrict network access to the affected service where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Affects Kit. SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
2DescriptionGitHub Advisory
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.
Blast Radius
ecosystem impact- 1 npm packages depend on @sveltejs/kit (1 direct, 0 indirect)
Ecosystem-wide dependent count for version 2.49.0.
Executive ViewAI
Organizations using SvelteKit face notable risk from CVE-2026-22803 rated CVSS 7.5. Exploitation could compromise the security of affected deployments. A patch is available and should be applied as part of regular vulnerability management.
Apply vendor patch. If immediate patching is not feasible: (1) Implement network-level access controls to limit exposure; (2) Enable enhanced monitoring and alerting; (3) Apply principle of least privilege.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)GitHub Advisory
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Exploit-DB