CyberSecBulletin
CVE-2026-127277NVD status: Deferred

EA8100: Improper Initialization

CVE-2026-127277 is a critical-severity improper initialization vulnerability in EA8100 from Linksys, with a CVSS 3.1 base score of 10.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected EA8100 versions: 1.0.3.216940. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.56% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of EA8100 you run against the affected versions below, and install the vendor's latest release.
  2. 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
LinksysEA81001.0.3.216940Not stated

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
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (vuldb.com).

Scoring systemScoreSeverityScored by
CVSS 4.09.3CriticalCNA (vuldb.com)
CVSS 3.110.0CriticalCNA (vuldb.com)
CVSS 2.010.0HighCNA (vuldb.com)

Official description

A security flaw has been discovered in Linksys EA8100 1.0.3.216940. The affected element is an unknown function of the file etc/init.d/service_smbd.sh of the component SMB Service. Performing a manipulation of the argument ANON_ACCESS results in improper initialization. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

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

The underlying weakness: Improper Initialization

The product does not initialize or incorrectly initializes a resource.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable's type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.
  • Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.
  • Explicitly initialize all your variables and other data stores, either during declaration or just before the first usage.

More Improper Initialization vulnerabilities (CWE-665)

Timeline

  1. CVE record published.

References

Other vulnerabilities in EA8100

All EA8100 vulnerabilities

Recent Improper Initialization vulnerabilities

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