CVE-2026-123807

CRITICAL 1 PoC
INFO Priority: 0.05 BB Relevance: 90/100
Published: 2026-11-09 Modified: 2026-11-12 First seen: 2026-11-09 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: High
I: High
A: High

Description

Signal K Server is a server application that runs on a central hub in a boat. From 2.0.0 until 2.34.0 for Signal K Server and from 1.0.0 until 1.5.3 for @signalk/resources-provider, the v2 REST route GET /signalk/v2/api/resources/:resourceType/:resourceId accepts an unsafe resourceId that can escape the intended resource directory. The route passes the attacker-controlled resourceId through src/api/resources/index.ts to FileStore.getResource() in packages/resources-provider-plugin/src/filestorage.ts without adequate path containment, allowing arbitrary JSON files reachable by the server to be read. Related PUT and DELETE resource operations can write or delete files outside the storage root. Deployments with allow_readonly enabled permit anonymous reads, while other deployments require a readonly user token. Reading security.json exposes the HS256 JWT signing secret and password hashes, allowing an attacker to forge an administrator token. Administrative access to POST /skServer/providers can then create an Execute provider that runs commands with the server process privileges and persists its configuration across restarts. This issue is fixed in Signal K Server 2.34.0 and @signalk/resources-provider 1.5.3.

Affected Software (4)

VendorProductVersion
@signalk resources-provider >= 1.0.0, < 1.5.3
@signalk resources-provider >= 1.0.0, < 1.5.3
SignalK signalk-server >= 2.0.0, < 2.34.0
SignalK signalk-server >= 2.0.0, < 2.34.0

Proof of Concept (1)

Bug Bounty Relevance

90 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction
✓ PoC available (1)

CVSS Score

9.8 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.54%
Raw Score 0.005360
Percentile 45.8%
Date 2026-11-13

EPSS Trend

2026-11-13
0.00536
2026-11-12
0.00536
2026-11-10
0.00536

Intelligence Sources

mitre ref →
nvd ref →