Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessObserve or predict cookie generation
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DeliverySpoof source IP in ClientHello
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ExploitReplay valid predicted cookie
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ExecutionBypass DTLS anti-spoofing check
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ImpactForce handshake state / reflection
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A04:2025 - Cryptographic Failures
ASVS 5.0
V11 - Cryptography Cryptographic random values
|
| Exploitation Conditions | Requires a NetX Secure deployment acting as a DTLS server that issues HelloVerifyRequest cookies (the stateless DTLS anti-spoofing exchange, typically DTLS 1.0/1.2 servers). Exploitation is remote and unauthenticated (PR:N/UI:N) but limited by high attack complexity (AC:H): the attacker must predict or reconstruct the weakly-random cookie value, which depends on the strength and seeding of NetX Secure's cookie/RNG generation. It only matters where DTLS cookie exchange is relied upon for source-address validation/anti-amplification; TLS-over-TCP paths and configurations not using DTLS cookies are unaffected. |
| Impact | This is a moderate, narrow-trigger weakness rather than a high-real-risk priority. The vendor CVSS 4.0 vector (AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L, 6.3) correctly captures a network-reachable, unauthenticated flaw with meaningful attack complexity (AC:H) and only low integrity and low availability impact - no confidentiality loss (VC:N). CWE-330 (insufficiently random values) fits: DTLS's HelloVerifyRequest cookie exists specifically to defeat source-address spoofing and amplification, so a predictable cookie undermines that anti-spoofing control rather than leaking data. No EPSS score, no CISA KEV listing, and no public exploit are present in the provided data, so exploitation status is 'no public exploit identified at time of analysis.' AC:H reflects that an attacker must reliably predict or reconstruct the cookie generation state, which is non-trivial and reduces practical exploitability. Note a data conflict: the 'Information Disclosure' tag contradicts the vector's VC:N - this is an anti-spoofing/randomness weakness, not a disclosure issue, and should not be triaged as a confidentiality problem. |
| Exploit ScenarioDerived | An off-path attacker predicts the DTLS HelloVerifyRequest cookie that a NetX Secure server issues, then completes the stateless cookie exchange using a spoofed source IP address, defeating the anti-spoofing/anti-amplification protection DTLS cookies are meant to provide. This lets the attacker force the server to allocate handshake state for spoofed peers or use it as a reflector, degrading availability and integrity of connection state. No public proof-of-concept is identified, and the high attack complexity (cookie prediction) limits reliability. |
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Alert meAnalysisAIv1 – Sep 29, 2026
Eclipse NetX Duo's DTLS server implementation uses predictable HelloVerifyRequest cookies due to insufficient randomness (CWE-330), enabling unauthenticated remote attackers to bypass source-address validation and potentially facilitate amplification attacks. Affected deployments are those running NetX Secure as a DTLS server with cookie exchange enabled; exploitation requires high attack complexity and no public exploit or active exploitation has been identified. The independent assessment rates this as a moderate, narrow-trigger weakness.
RemediationAI
Apply the patch referenced in the Eclipse Foundation security advisory GHSA-j6gx-3j6v-3hm4 (https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-j6gx-3j6v-3hm4); the advisory should specify the fixed version. If immediate patching is not possible, consider disabling DTLS cookie exchange (HelloVerifyRequest) in NetX Secure configurations, but be aware this increases susceptibility to amplification attacks and should be combined with network-level rate limiting. Alternatively, restrict DTLS server access to trusted networks or disable DTLS server functionality if not required. These compensating controls have trade-offs: disabling cookies weakens anti-spoofing, while network restrictions may impact legitimate clients.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
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Technical ContextAI · show details
The vulnerability resides in the DTLS handshake's anti-spoofing mechanism, where the server responds to a ClientHello with a HelloVerifyRequest containing a cookie that the client must echo back. This cookie must be unpredictable to prevent an attacker from forging it and bypassing source-address validation, which is critical for mitigating amplification attacks. CWE-330 (Use of Insufficiently Random Values) indicates that NetX Secure generates these cookies using a weak randomness source, making them predictable. The CPE cpe:2.3:a:eclipse_foundation:netxduo:*:*:*:*:*:*:*:* identifies Eclipse NetX Duo as the affected product, specifically its NetX Secure component. The CVSS 4.0 vector (AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N) and the independent CVSS 3.1 vector (AV:N/AC:H/PR:N/UI:N/S:N/C:N/I:L/A:L) both reflect remote, unauthenticated exploitation with high complexity and limited integrity/availability impact.
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Severity by source
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
Remote unauthenticated (AV:N/PR:N) but cookie prediction makes AC:H; predictable cookie bypasses anti-spoofing affecting integrity/availability of connection state (I:L/A:L), no data disclosure (C:N).
Primary rating from Vendor (eclipse).
CVSS VectorVendor: eclipse
DescriptionCVE.org
Predictable DTLS HelloVerifyRequest Cookie in NetX Secure
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
EUVD-2026-89182
GHSA-3fp7-fjmc-gqr7
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB