Medium Memory corruption

CVE-2026-102720 — Out-of-bounds Read in Eclipse Foundation Threadx Netx Duo

A DHCP server, or anyone on the LAN who answers a DISCOVER first, can make the client read about a kilobyte past the end of the received message. The option walk keeps a pointer and an offset in step, and the only bound check uses the offset: ```c /* addons/dhcp/nxd_dhcp_client.c:7538, 7572 */ while (i < length - 1) { ... size = *(++data); /* data moves 1: type -> length byte */ data += size + 1; /* data moves size + 1 more */ i += size + 1; /* i moves only size + 1 */ } ``` A TLV option occupies size + 2 bytes. `data` is advanced by size + 2 in total, `i` by size + 1, so the offset falls one byte behind the real read position for every option the walk skips. After enough skipped options the check `i < length - 1` still holds while `data` is already past the end of the message, and the subsequent read of the type and length bytes comes from whatever follows. A single OFFER carrying a long run of skippable options is enough: ``` ERROR: AddressSanitizer: heap-buffer-overflow READ of size 1 at 0x61b000000794 thread T5 #0 _nx_dhcp_search_buffer addons/dhcp/nxd_dhcp_client.c:7541 #1 _nx_dhcp_get_option_value addons/dhcp/nxd_dhcp_client.c:7082 0x61b000000794 is located 164 bytes to the right of 1648-byte region ``` A well formed OFFER through the same path is handled normally, the client records the offer and moves to REQUESTING, so the difference is the option layout rather than the harness. The read runs in the DHCP client thread while the client is still unconfigured, so it happens on every boot in reach of a hostile DHCP responder. The values read are used to configure the interface, which is how the disclosed bytes become observable. Advance `i` by size + 2, or derive the bound from `data` rather than keeping a second counter.

Published Sep 29, 2026 · Updated Oct 16, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: eclipse

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

—

No EPSS score.

Affects

Eclipse Foundation

Threadx Netx Duo

CVSS base

5.3

Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Eclipse Foundation Threadx Netx Duo).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Eclipse Foundation	Threadx Netx Duo	≤ 6.5.1	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Adjacent

Attack complexity

Low

Attack requirements

None

Privileges required

None

User interaction

None

Scope

Confidentiality (vulnerable system)

Low

Integrity (vulnerable system)

None

Availability (vulnerable system)

Low

Confidentiality (subsequent)

None

Integrity (subsequent)

None

Availability (subsequent)

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
5.3	CVSS 4.0	Medium	—	—	emo@eclipse.org via NIST National Vulnerability Database
5.3	CVSS 4.0	Medium	—	—	eclipse via CVE Program (cve.org) e CISA ADP

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

(score shown at the top: emo@eclipse.org)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-125 · Out-of-bounds Read

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

endpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

2026
Affected products added · eclipse foundation/eclipse-threadx/netxduo
Oct 16, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 16, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 15, 2026
CVSS changed · 5.3
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Awaiting Analysis
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 29, 2026 · eclipse

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

1 on the record

github.com/eclipse-threadx/netxduo/security/advisories/GHSA-8hj5-p46x-5h28
NIST National Vulnerability Database

Elsewhere on this site

Eclipse Foundation
every CVE for this vendor

Memory corruption
same class

CWE-125
other pages naming this weakness

Related CVEs (same products)

Critical CVE-2026-103416 Out-of-bounds Write in Eclipse Foundation Threadx Netx Duo 8d
High CVE-2026-102716 Missing Release of Memory after Effective Lifetime in Eclipse Foundation Threadx Netx Duo 16d
High CVE-2026-102715 mDNS string-cache lookup matches on slot size, so a peer name aliases a shorter one and the response encoder writes past the packet 16d
High CVE-2026-11576 The security fix for CVE-2025-0728 in eclipse-threadx NetX Duo refactors error handling… Jun 19, 2026
High CVE-2025-55102 Uncontrolled Resource Consumption in Eclipse Foundation Threadx Netx Duo Jan 27, 2026
Critical CVE-2025-55086 Out-of-bounds Read in Eclipse Foundation Threadx Netx Duo Oct 20, 2025

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No FIRST EPSS score.
No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-102720 is "Out-of-bounds Read in Eclipse Foundation Threadx Netx Duo", rated Medium. It affects Threadx Netx Duo (Eclipse Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.3 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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