RCE in Gudong2003 Xianyu-Auto-Reply-Fix
CVE-2026-118691
xianyu-auto-reply-fix through 2.0.7 contains a missing authorization vulnerability in the POST /send-message endpoint that allows unauthenticated attackers to send messages from other users' accounts using publicly known default API secrets. Attackers can supply the hard-coded api_key and another user's cookie_id, plus chosen chat_id, to_user_id and message values, to send arbitrary Xianyu messages to buyers from that merchant account.
Published .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/GuDong2003/xianyu-auto-reply-fix/issues/116 (issue-tracking)
- github.com/GuDong2003/xianyu-auto-reply-fix (product)
- github.com/GuDong2003/xianyu-auto-reply-fix/blob/v2.0.7/reply_server.py (technical-description)
- github.com/GuDong2003/xianyu-auto-reply-fix/blob/v2.0.7/db_manager.py (technical-description)
- github.com/GuDong2003/xianyu-auto-reply-fix/commit/999cfe61c401322d9893eb81ad1a… (patch)
- www.vulncheck.com/advisories/xianyu-auto-reply-fix-through-2.0.7-unauthenticate… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-118691?
- CVE-2026-118691 is a low-severity vulnerability in Gudong2003 Xianyu-Auto-Reply-Fix, classified under Initialization of a Resource with an Insecure Default. CVSS score: 3.7/10. Published 2026-10-28.
- How severe is CVE-2026-118691?
- Low severity. CVSS v3 base score is 3.7 out of 10.