CVE-2026-18536

Data::Entropy versions before 0.010 for Perl read remote entropy sources over plain HTTP

Published Aug 1, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

Vendor Workaround

Deployments should not use the RandomOrg or RandomnumbersInfo sources, as these are flawed. They have been removed from Data::Entropy 0.010. (There was a change to use HTTPS to connect to these sources in version 0.009 that did not work.) Note that Data::Entropy has been deprecated since version 0.008. Users are advised to migrate to alternative solutions that use system sources of random data, such as Crypt::SysRandom, Crypt::URandom or Crypt::PRNG.

Tracking

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Advisories

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History
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Rrwo
Rrwo data::entropy
Vendors & Products Rrwo
Rrwo data::entropy
Type Values Removed Values Added
Description 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.
Title Data::Entropy versions before 0.010 for Perl read remote entropy sources over plain HTTP
Weaknesses CWE-319
CWE-353
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
CPANSec
Published
Updated
Aug 3, 2026, 7:55 PM
Reserved
Jul 31, 2026, 8:31 PM
Status
Analyzed
Published
Aug 1, 2026, 11:16 AM
Modified
Oct 23, 2026, 11:10 PM
Severity
Important
Public date
Aug 1, 2026, 10:35 AM