Is CVE-2026-27203 in the CISA KEV catalog?

No. CVE-2026-27203 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-27203?

CVE-2026-27203 has a CVSS v3 base score of 8.3 (HIGH).

What is the EPSS score for CVE-2026-27203?

CVE-2026-27203 has an EPSS score of 0.36% (28th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix or mitigate CVE-2026-27203?

No published fix for CVE-2026-27203 has been found yet. Check the linked vendor advisories for guidance as it becomes available.

CVE & CISA-KEV Catalog

CVE-2026-27203

HIGH

8.3

CVSS v3

NVD

Description

eBay API MCP Server is an open source local MCP server providing AI assistants with comprehensive access to eBay's Sell APIs. All versions are vulnerable to Environment Variable Injection through the updateEnvFile function. The ebay_set_user_tokens tool allows updating the .env file with new tokens. The updateEnvFile function in src/auth/oauth.ts blindly appends or replaces values without validating them for newlines or quotes. This allows an attacker to inject arbitrary environment variables into the configuration file. An attacker can inject arbitrary environment variables into the .env file. This could lead to configuration overwrites, Denial of Service, and potential RCE. There was no fix for this issue at the time of publication.

CWE-15 CWE-74Injection

How to fix

No published remediation has been found for this vulnerability's affected products yet.

Mitigation guidance may be in the linked vendor advisories in the References section below.

TridentStack Control tracks known vulnerabilities across your Windows, macOS, and Linux fleet and shows the fix as soon as one is published. See how it works

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H

Exploit Intelligence

0.36%probability of exploitation in 30 days

28thpercentile

Low risk: more likely to be exploited than 28% of all known CVEs.

References

Other references2

Related Vulnerabilities

Other CWE-15 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2026-41176	Critical	9.8	35%	-	Fix
CVE-2024-39280	Critical	9.1	34%	-	-
CVE-2023-50252	High	8.3	24%	-	Fix
CVE-2024-38666	Critical	9.1	19%	-	-
CVE-2024-51544	High	8.2	14%	-	Fix
CVE-2024-10979	High	8.8	4.4%	-	Fix

Embed a live status badge for CVE-2026-27203

Markdown

[![CVE-2026-27203](https://tridentstack.com/cve/badge/CVE-2026-27203.svg)](https://tridentstack.com/cve/CVE-2026-27203)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-27203"><img src="https://tridentstack.com/cve/badge/CVE-2026-27203.svg" alt="CVE-2026-27203"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it works Start freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-02-23.