VulnerabilityPublished 11 Aug 2025Updated 17 Jan 2026

CVE-2025-40920: ETHER Catalyst::Authentication::Credential::HTTP · Generation of Predictable Numbers or Identifiers

Affects ETHER Catalyst::Authentication::Credential::HTTPSource CVE Database V5

Not known to be exploited · CVSS 8.6 High.

Data as of 26 Oct 2026, 11:42 UTC

CVSS 3.1 base score

8.6High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: Low
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

cwe-338

What to do

Affected software

Product	Affected	Fixed in
ETHER Catalyst::Authentication::Credential::HTTP	Affected =0.06	Fixed in–

AI-suggested

European organizations should immediately audit their use of Catalyst::Authentication::Credential::HTTP modules to identify affected versions (1.018 and earlier, specifically 0.06). Since no official patches are currently linked, developers should modify the nonce generation code to replace Data::UUID-based version 3 UUIDs with nonces generated from a cryptographically secure random number generator, such as Perl's Crypt::Random or other libraries compliant with RFC 7616. Implementing nonce generation using secure random sources will prevent predictability and strengthen authentication security. Additionally, organizations should monitor their web authentication logs for unusual or repeated nonce values that could indicate attempted exploitation. Applying strict access controls and network segmentation around affected services can reduce exposure. Finally, maintain vigilance for vendor updates or patches and apply them promptly once available. Incorporating security code reviews focusing on cryptographic practices in authentication modules is recommended to prevent similar issues.

Description

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 for security, as per RFC 9562. * The nonces should be generated from a strong cryptographic source, as per RFC 7616.

Impact

For European organizations, this vulnerability poses a significant risk to web applications and services that utilize the Catalyst::Authentication::Credential::HTTP module for HTTP authentication. Exploitation could lead to unauthorized access by allowing attackers to predict or replay authentication nonces, compromising sensitive data confidentiality and potentially disrupting service availability. Sectors such as finance, healthcare, government, and critical infrastructure that rely on Perl-based web frameworks for secure authentication are particularly vulnerable. The predictability of nonces may facilitate man-in-the-middle or replay attacks, undermining trust in authentication mechanisms and potentially leading to data breaches or service interruptions. Given the high CVSS score and network exploitable nature, attackers can remotely exploit this vulnerability without authentication or user interaction, increasing the threat surface. The absence of known exploits in the wild suggests a window for proactive mitigation before widespread exploitation occurs.

CWE-340Generation of Predictable Numbers or Identifiers (opens in a new tab)
Class weaknessOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product uses a scheme that generates numbers or identifiers that are more predictable than required.
OWASP Cheat Sheets
Forgot Password (opens in a new tab)
Transport Layer Protection (opens in a new tab)
User Privacy Protection (opens in a new tab)
Password Storage (opens in a new tab)
Cryptographic Storage (opens in a new tab)
OWASP ASVS 4.0.3
V2.3.1 (opens in a new tab)
V2.6.2 (opens in a new tab)
V2.7.6 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Jan 2026, 07:13 UTC

WeaknessesCWE-340

Technical details

References

Community reviews

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