CVE-2026-18536: Rrwo Data::entropy

High severity, CVSS 7.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Data::Entropy versions before 0.010 for Perl read remote entropy sources over plain HTTP. The Data::Entropy::RawSource::RandomOrg and Data::Entropy::RawSource::RandomnumbersInfo remote sources are accessed over plain HTTP. The Data::Entropy::RawSource::RandomOrg integrity check trivially matches any non-empty byte string. Any on-path attacker, such as open WiFi, a compromised ISP, captive portal, or a hostile egress proxy substitutes the response and thereby chooses the bytes returned by rand_bits and rand_int for every application that selected one of these sources via with_entropy_source. The _checkbuf method response is equally attacker-controlled, so the retry/sleep behaviour is steerable too.

Affected products

• Rrwo Data::entropy: before 0.010 (fixed in 0.010)

Published 2026-08-01. Last modified 2026-08-07.