CVE-2025-15604: Tokuhirom Amon2 vulnerability (CVSS 9.8)

Description

Amon2 versions before 6.17 for Perl use an insecure random_string implementation for security functions. In versions 6.06 through 6.16, the random_string function will attempt to read bytes from the /dev/urandom device, but if that is unavailable then it generates bytes by concatenating a SHA-1 hash seeded with the built-in rand() function, the PID, and the high resolution epoch time. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. Before version 6.06, there was no fallback when /dev/urandom was not available. Before version 6.04, the random_string function used the built-in rand() function to generate a mixed-case alphanumeric string. This function may be used for generating session ids, generating secrets for signing or encrypting cookie session data and generating tokens used for Cross Site Request Forgery (CSRF) protection.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Tokuhirom Amon2< 6.17

Remediation

Fixed in

Tokuhirom Amon2≥ 6.17

Patch & vendor advisories

https://github.com/tokuhirom/Amon/pull/135

References

https://github.com/tokuhirom/Amon/pull/135Issue TrackingPatch
https://metacpan.org/release/TOKUHIROM/Amon2-6.17/changesProduct
https://metacpan.org/release/TOKUHIROM/Amon2-6.17/diff/TOKUHIROM/Amon2-6.16#lib/Amon2/Util.pmProduct
https://security.metacpan.org/docs/guides/random-data-for-security.htmlThird Party Advisory
http://www.openwall.com/lists/oss-security/2026/03/28/4Mailing ListThird Party Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2025-15604 being actively exploited?

CVE-2025-15604 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.52%.

How severe is CVE-2025-15604?

CVE-2025-15604 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.52% probability of exploitation.

Which products are affected by CVE-2025-15604?

Affected products include Tokuhirom Amon2.

How do I fix CVE-2025-15604?

Upgrade affected software to a fixed version, for example Tokuhirom Amon2 6.17 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2025-15604 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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