CVE-2026-5087

CVE-2026-5087 is a high-severity vulnerability in Jjnapiork Pagi with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-338.

Key facts

Description

PAGI::Middleware::Session::Store::Cookie versions through 0.001003 for Perl generates random bytes insecurely. PAGI::Middleware::Session::Store::Cookie attempts to read bytes from the /dev/urandom device directly. If that fails (for example, on systems without the device, such as Windows), then it will emit a warning that recommends the user install Crypt::URandom, and then return a string of random bytes generated by the built-in rand function, which is unsuitable for cryptographic applications. This modules does not use the Crypt::URandom module, and installing it will not fix the problem. The random bytes are used for generating an initialisation vector (IV) to encrypt the cookie. A predictable IV may make it easier for malicious users to decrypt and tamper with the session data that is stored in the cookie.

Frequently asked questions

What is CVE-2026-5087?
PAGI::Middleware::Session::Store::Cookie versions through 0.001003 for Perl generates random bytes insecurely. PAGI::Middleware::Session::Store::Cookie attempts to read bytes from the /dev/urandom device directly. If that fails (for example, on systems without the device, such as Windows), then it will emit a warning that recommends the user install Crypt::URandom, and then return a string of random bytes generated by the built-in rand function, which is unsuitable for cryptographic applications. This modules does not use the Crypt::URandom module, and installing it will not fix the problem. The random bytes are used for generating an initialisation vector (IV) to encrypt the cookie. A predictable IV may make it easier for malicious users to decrypt and tamper with the session data that is stored in the cookie.
How severe is CVE-2026-5087?
CVE-2026-5087 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-5087 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5087?
CVE-2026-5087 affects Jjnapiork Pagi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5087?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-5087 have an EU (EUVD) identifier?
Yes. CVE-2026-5087 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17531.
When was CVE-2026-5087 published?
CVE-2026-5087 was published on 2026-03-31 and last updated on 2026-06-17.

References

Affected products (1)

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