FKIE_CVE-2026-66062

Vulnerability from fkie_nvd - Published: 2026-08-07 17:17 - Updated: 2026-08-07 22:16
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.70.2, the content negotiation header parser used by SvelteKit's request handling (for headers such as Accept) uses a regular expression vulnerable to quadratic backtracking, so a maliciously crafted header value can cause excessive CPU consumption and degrade or deny service. Version 2.70.2 fixes the issue.
References
security-advisories@github.comhttps://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5
security-advisories@github.comhttps://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2
security-advisories@github.comhttps://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "kit",
          "vendor": "sveltejs",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.70.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.70.2, the content negotiation header parser used by SvelteKit\u0027s request handling (for headers such as Accept) uses a regular expression vulnerable to quadratic backtracking, so a maliciously crafted header value can cause excessive CPU consumption and degrade or deny service. Version 2.70.2 fixes the issue."
    }
  ],
  "id": "CVE-2026-66062",
  "lastModified": "2026-08-07T22:16:59.637",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-66062",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-07T20:58:04.458547Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-07T17:17:06.340",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1333"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.