CVE-2025-40920
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:LSummary
CVE-2025-40920 is a high-severity PRNG (CWE-338) vulnerability. Its CVSS base score is 8.6 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Forge Web Credentials (T1606); ranked at the 34th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SC-12 (Cryptographic Key Establishment and Management) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-40920 is a vulnerability in Catalyst::Authentication::Credential::HTTP versions 1.018 and earlier, a Perl module used for HTTP authentication credentials. The issue stems from nonce generation relying on the Data::UUID library, which produces version 3 UUIDs derived from known information without a strong cryptographic randomness source. This approach is unsuitable for security contexts, as noted in RFC 9562, and fails to meet RFC 7616 requirements for cryptographically secure nonces in HTTP authentication.
The vulnerability carries a CVSS v3.1 base score of 8.6 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L), indicating exploitation is possible remotely over the network with low complexity, no privileges, no user interaction, and unchanged scope. Attackers can leverage the predictable nonces to achieve high confidentiality impact, such as bypassing authentication mechanisms, alongside low integrity and availability impacts. It maps to CWE-338 (uses of weak cryptography) and CWE-340 (predictable generation of identifiers).
Mitigation is addressed in the project's GitHub repository via commit ad2c03aad95406db4ce35dfb670664ebde004c18 and pull request #1, which update the nonce generation process. The vulnerable code is visible in the source at metacpan.org for version 1.018. Additional guidance appears in RFC 7616 section 5.12 and RFC 9562 security considerations, emphasizing strong cryptographic sources for nonces.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-24168
Vulnerability Data
Catalyst::Authentication::Credential::HTTP versions 1.018 and earlier for Perl generate nonces using the Perl Data::UUID library. * Data::UUID does not use a strong cryptographic source for generating UUIDs. * Data::UUID returns v3 UUIDs, which are generated from known information and are unsuitable…
more
for security, as per RFC 9562. * The nonces should be generated from a strong cryptographic source, as per RFC 7616.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 9 hardening rules · 4 OS baselines
V7.2.3V11.5.1V11.3.4
Mitigating Controls (NIST 800-53 r5) AI
Requiring specific approved cryptography for protection directly mandates use of strong PRNGs instead of weak ones.
Developer testing and evaluation can discover predictable number generation through targeted analysis or fuzzing of identifier creation routines.
Cryptographic key establishment and management mandates proper entropy and randomness during generation, directly stopping predictable identifiers at the source.
Authenticator management requires secure initial distribution and handling of authenticators, structurally preventing predictable values from being usable.
Engineering principles applied during design and development include selection of cryptographically strong random number generation.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices explicitly require cryptographically strong RNG selection and usage in security contexts.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Mandates use of approved cryptographic controls, directly requiring cryptographically strong RNGs.
Security testing can detect use of weak random number generators.
Secure SDLC processes should catch weak PRNG usage during design and code review.
Application security requirements can specify cryptographically strong random number generation.
Secure engineering principles include selection of appropriate cryptographic primitives.
Secure coding standards prohibit use of weak PRNGs in security contexts.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (3 rules)
- V-248524 OL 8 must implement NIST FIPS-validated cryptography for the following: To provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-340
- V-248563 The OL 8 SSH server must be configured to use strong entropy. prevents CWE-338
- V-248600 OL 8 must have the packages required to use the hardware random number generator entropy gatherer service. prevents CWE-340
RHEL 7 (1 rule)
- V-204497 The Red Hat Enterprise Linux operating system must implement NIST FIPS-validated cryptography for the following: to provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-340
RHEL 8 (2 rules)
- V-230253 RHEL 8 must ensure the SSH server uses strong entropy. prevents CWE-338
- V-244527 RHEL 8 must have the packages required to use the hardware random number generator entropy gatherer service. prevents CWE-340
Ubuntu 22.04 (1 rule)
- V-260650 Ubuntu 22.04 LTS must implement NIST FIPS-validated cryptography to protect classified information and for the following: To provision digital signatures, to generate cryptographic hashes, and to protect unclassified information requiring confidentiality and cryptographic protection in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-338