CVE-2026-18536

Status: AnalyzedHigh (7.5)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Base score: 7.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.15%
Percentile among all scored CVEs: 4
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1557 Adversary-in-the-Middlecredential access · collection85 %
Primary impactT1005 Data from Local Systemcollection90 %
Secondary impactT1565 Data Manipulationimpact75 %

Ataque MITM sobre HTTP plain (CWE-319) con integridad débil (CWE-353): on-path attacker sustituye respuestas de entropía. Impacto: lectura de datos aleatorios controlados y manipulación de flujo de entropía en aplicaciones dependientes.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Network Segmentation Encrypt Sensitive Information User Training Restrict File and Directory Permissions Remote Data Storage Network Intrusion Prevention

Affected technologies (1)

Rrwo — Data\

CWEs

CWE-319, CWE-353

References

Raw JSON (NVD)

Show

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