LY Armeria up to 1.42.x xds link following

Summaryinfo

A vulnerability was found in LY Armeria up to 1.42.x and classified as problematic. This vulnerability affects unknown code of the component xds. Executing a manipulation can lead to link following. The identification of this vulnerability is CVE-2026-121819. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in LY Armeria up to 1.42.x. It has been declared as problematic. This vulnerability affects an unknown code of the component xds. The manipulation with an unknown input leads to a link following vulnerability. The CWE definition for the vulnerability is CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. As an impact it is known to affect confidentiality. CVE summarizes:

A vulnerability has been identified in armeria-xds versions 1.40.0 through 1.42.0, where DataSourcePolicy checks filename containment without resolving symbolic links, allowing a compromised or semi-trusted xDS control plane to cause the xDS client to read files outside configured allowed root directories when a symbolic link inside an allowed directory points outside it. In deployments using a credential injector, header-compatible text secrets may be exposed to an attacker-observable upstream.

The advisory is shared for download at line.github.io. This vulnerability was named CVE-2026-121819 since 11/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version 1.43.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• LY

Name

• Armeria

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35
• 1.36
• 1.37
• 1.38
• 1.39
• 1.40
• 1.41
• 1.42

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion