CVE-2026-64647 (GCVE-0-2026-64647)
Vulnerability from cvelistv5 – Published: 2026-07-27 19:11 – Updated: 2026-07-27 19:27
VLAI
EPSS
VEX
Title
Next.js: Response Body Cache Confusion with Invalid UTF-8 Request Bodies
Summary
Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST's response body would then leak to unauthorized requests. Though the request itself will not be deduped. This is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for 삃삃 and 섄섄 in the request body would share the same cache. This issue has been fixed in versions 15.5.21 and 16.2.11.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-116 - Improper Encoding or Escaping of Output
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/vercel/next.js/security/adviso… | x_refsource_CONFIRM |
| https://github.com/vercel/next.js/pull/96008 | x_refsource_MISC |
| https://github.com/vercel/next.js/commit/025bf4a5… | x_refsource_MISC |
| https://github.com/vercel/next.js/releases/tag/v15.5.21 | x_refsource_MISC |
| https://github.com/vercel/next.js/releases/tag/v16.2.11 | x_refsource_MISC |
Impacted products
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-64647",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-27T19:27:08.369919Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-27T19:27:13.932Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "next.js",
"vendor": "vercel",
"versions": [
{
"status": "affected",
"version": "\u003e= 13.0.0, \u003c 15.5.21"
},
{
"status": "affected",
"version": "\u003e= 16.0.0, \u003c 16.2.11"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST\u0027s response body would then leak to unauthorized requests. Though the request itself will not be deduped. This is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for \uc083\uc083 and \uc104\uc104 in the request body would share the same cache. This issue has been fixed in versions 15.5.21 and 16.2.11."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 6.3,
"baseSeverity": "MEDIUM",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "LOW"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-116",
"description": "CWE-116: Improper Encoding or Escaping of Output",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-27T19:11:28.477Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q"
},
{
"name": "https://github.com/vercel/next.js/pull/96008",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/vercel/next.js/pull/96008"
},
{
"name": "https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082"
},
{
"name": "https://github.com/vercel/next.js/releases/tag/v15.5.21",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/vercel/next.js/releases/tag/v15.5.21"
},
{
"name": "https://github.com/vercel/next.js/releases/tag/v16.2.11",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/vercel/next.js/releases/tag/v16.2.11"
}
],
"source": {
"advisory": "GHSA-4633-3j49-mh5q",
"discovery": "UNKNOWN"
},
"title": "Next.js: Response Body Cache Confusion with Invalid UTF-8 Request Bodies"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-64647",
"datePublished": "2026-07-27T19:11:28.477Z",
"dateReserved": "2026-07-20T17:11:30.895Z",
"dateUpdated": "2026-07-27T19:27:13.932Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"nvd": "{\"cve\":{\"id\":\"CVE-2026-64647\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-07-27T19:17:21.627\",\"lastModified\":\"2026-07-27T20:16:40.447\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST\u0027s response body would then leak to unauthorized requests. Though the request itself will not be deduped. This is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for \uc083\uc083 and \uc104\uc104 in the request body would share the same cache. This issue has been fixed in versions 15.5.21 and 16.2.11.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"vercel\",\"product\":\"next.js\",\"versions\":[{\"version\":\"\u003e= 13.0.0, \u003c 15.5.21\",\"status\":\"affected\"},{\"version\":\"\u003e= 16.0.0, \u003c 16.2.11\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/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\",\"baseScore\":6.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"LOW\",\"vulnIntegrityImpact\":\"LOW\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-07-27T19:27:08.369919Z\",\"id\":\"CVE-2026-64647\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-116\"}]}],\"references\":[{\"url\":\"https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vercel/next.js/pull/96008\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vercel/next.js/releases/tag/v15.5.21\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vercel/next.js/releases/tag/v16.2.11\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q\",\"source\":\"security-advisories@github.com\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-64647\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-27T19:27:08.369919Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-27T19:27:11.150Z\"}}], \"cna\": {\"title\": \"Next.js: Response Body Cache Confusion with Invalid UTF-8 Request Bodies\", \"source\": {\"advisory\": \"GHSA-4633-3j49-mh5q\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 6.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"LOW\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"LOW\"}}], \"affected\": [{\"vendor\": \"vercel\", \"product\": \"next.js\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003e= 13.0.0, \u003c 15.5.21\"}, {\"status\": \"affected\", \"version\": \"\u003e= 16.0.0, \u003c 16.2.11\"}]}], \"references\": [{\"url\": \"https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q\", \"name\": \"https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/vercel/next.js/pull/96008\", \"name\": \"https://github.com/vercel/next.js/pull/96008\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082\", \"name\": \"https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/vercel/next.js/releases/tag/v15.5.21\", \"name\": \"https://github.com/vercel/next.js/releases/tag/v15.5.21\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/vercel/next.js/releases/tag/v16.2.11\", \"name\": \"https://github.com/vercel/next.js/releases/tag/v16.2.11\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST\u0027s response body would then leak to unauthorized requests. Though the request itself will not be deduped. This is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for \\uc083\\uc083 and \\uc104\\uc104 in the request body would share the same cache. This issue has been fixed in versions 15.5.21 and 16.2.11.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-116\", \"description\": \"CWE-116: Improper Encoding or Escaping of Output\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-07-27T19:11:28.477Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-64647\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-27T19:27:13.932Z\", \"dateReserved\": \"2026-07-20T17:11:30.895Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-07-27T19:11:28.477Z\", \"assignerShortName\": \"GitHub_M\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
Loading…
Loading…