CyberSecBulletin
CVE-2026-3416NVD status: Analyzed

WSO2 API Manager: Use of Insufficiently Random Values

CVE-2026-3416 is a high-severity use of insufficiently random values vulnerability in WSO2 API Manager from WSO2, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 4.1.0.253, 4.2.0.193, 4.3.0.104 as the first without the flaw, so updating WSO2 API Manager to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update WSO2 API Manager to 4.1.0.253 or 4.2.0.193 or 4.3.0.104 or 4.4.0.68, whichever matches your release line, or a later version.
  2. Update WSO2 API Control Plane to 4.5.0.53 or a later version.
  3. Update API Control Plane to 4.5.0.53 or a later version.
  4. Read the advisory on security.docs.wso2.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
WSO2WSO2 API Manager4.1.0 up to, but not including, 4.1.0.253; 4.2.0 up to, but not including, 4.2.0.193; 4.3.0 up to, but not including, 4.3.0.104; 4.4.0 up to, but not including, 4.4.0.68; 4.5.0 up to, but not including, 4.5.0.524.1.0.253, 4.2.0.193, 4.3.0.104, 4.4.0.68, 4.5.0.52
WSO2WSO2 API Control Plane4.5.0 up to, but not including, 4.5.0.534.5.0.53
WSO2API Control Plane4.5.0 up to, but not including, 4.5.0.534.5.0.53
WSO2API Manager4.1.0 up to, but not including, 4.1.0.253; 4.2.0 up to, but not including, 4.2.0.193; 4.3.0 up to, but not including, 4.3.0.104; 4.4.0 up to, but not including, 4.4.0.68; 4.5.0 up to, but not including, 4.5.0.524.1.0.253, 4.2.0.193, 4.3.0.104, 4.4.0.68, 4.5.0.52

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.9MediumCNA
CVSS 3.17.5HighNVD

Official description

The API Publisher component previously used a non-cryptographic pseudorandom number generator (PRNG) to create shared secrets for Webhook HMAC validation. This PRNG lacks sufficient entropy for security-sensitive operations, allowing a sophisticated attacker to predict future secrets. This enables malicious actors to forge event payloads with valid HMAC signatures, bypassing the API Gateway's authenticity verification. Successful exploitation could allow an attacker to predict shared secrets used for Webhook HMAC validation and forge event payloads with valid signatures. This may enable bypassing API Gateway authenticity checks, leading to unauthorized event injection, data manipulation, or downstream system compromise.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Insufficiently Random Values

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

How developers prevent this class of flaw

  • Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds. In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts. Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a random enough number.
  • Consider a PRNG that re-seeds itself as needed from high quality pseudo-random output sources, such as hardware devices.
  • Use products or modules that conform to FIPS 140-2 to avoid obvious entropy problems. Consult FIPS 140-2 Annex C (Approved Random Number Generators).

More Use of Insufficiently Random Values vulnerabilities (CWE-330)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in WSO2 API Manager

All WSO2 API Manager vulnerabilities

Recent Use of Insufficiently Random Values vulnerabilities

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