CVE-2026-13577 (GCVE-0-2026-13577)

Vulnerability from cvelistv5 – Published: 2026-07-20 07:11 – Updated: 2026-07-22 12:00
VLAI
Title
Dancer2 versions through 2.1.0 for Perl generate insecure session ids when required CSPRNG modules are unavailable
Summary
Dancer2 versions through 2.1.0 for Perl generate insecure session ids when required CSPRNG modules are unavailable. Dancer2::Core::Role::SessionFactory::generate_id silently falls back to a built-in rand-derived session id unless both Math::Random::ISAAC::XS and Crypt::URandom are available. The fallback session id is generated from a SHA-1 hash of a call to the built-in rand function, the absolute path of the Dancer2::Core::Role::SessionFactory module, an internal counter, the process id, the module instance memory address, and a shuffled string of characters (using the List::Util::shuffle function, which also uses the built-in rand function). These are all low-entropy and easily guessed sources. The built-in rand() function is seeded with 32-bits and considered unsuitable for security applications. Predictable session ids could allow an attacker to gain access to systems.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-340 - Generation of Predictable Numbers or Identifiers
  • CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator
Assigner
Impacted products
Vendor Product Version
CROMEDOME Dancer2 Affected: 0 , ≤ 2.1.0 (custom)
Create a notification for this product.
Show details on NVD website

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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