CVE-2026-110676
Full vulnerability record from the local CVENow database.
Description
Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by encoding exponent notation as full decimal digits under allow_bignum. With allow_bignum, a JSON number with a fraction or exponent decodes to a Math::BigFloat, which stores the exponent separately and so decodes cheaply. Encoding it untyped or as JSON_TYPE_FLOAT writes the plain decimal form with one digit per unit of exponent. Nothing bounds the exponent, so the 12-byte text [1e30000000] encodes to 30 MB. Untrusted JSON decoded with allow_bignum and encoded again can exhaust memory and CPU.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
9b29abf9-4ab0-4765-b253-1875cd9b441e
Published
2026-10-19 19:17:21.320000
Last modified
2026-10-29 17:17:59.987000
View original CVE JSON
{
"id": "CVE-2026-110676",
"sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"published": "2026-10-19T19:17:21.320",
"lastModified": "2026-10-29T17:17:59.987",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by encoding exponent notation as full decimal digits under allow_bignum.\n\nWith allow_bignum, a JSON number with a fraction or exponent decodes to a Math::BigFloat, which stores the exponent separately and so decodes cheaply. Encoding it untyped or as JSON_TYPE_FLOAT writes the plain decimal form with one digit per unit of exponent. Nothing bounds the exponent, so the 12-byte text [1e30000000] encodes to 30 MB.\n\nUntrusted JSON decoded with allow_bignum and encoded again can exhaust memory and CPU."
}
],
"affected": [
{
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"affectedData": [
{
"defaultStatus": "unaffected",
"collectionURL": "https://cpan.org/modules",
"packageName": "Cpanel-JSON-XS",
"modules": [
"Cpanel::JSON::XS"
],
"programFiles": [
"XS.xs"
],
"programRoutines": [
{
"name": "encode_rv"
},
{
"name": "encode_sv"
}
],
"repo": "https://github.com/rurban/Cpanel-JSON-XS",
"packageURL": "pkg:cpan/Cpanel-JSON-XS",
"versions": [
{
"version": "0",
"lessThan": "4.80",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 3.9,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-29T16:41:22.938408Z",
"id": "CVE-2026-110676",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-405"
}
]
}
],
"references": [
{
"url": "https://github.com/rurban/Cpanel-JSON-XS/commit/996ab96972b967a917536d291947b5f3cf42e960.patch",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
},
{
"url": "https://metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.80/changes",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}
]
}