[ CVE-2026-110676 · Published 19 Oct 2026 ]
Vulnerability
[ Description ]Official 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.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.