Description
Niefy wx-api through 0.8.2 contains an authentication bypass vulnerability that allows unauthenticated attackers to impersonate WeChat fans by supplying a raw openid cookie to fan-facing controllers. Attackers knowing a victim's openid can call /wxUser/getUserInfo and /wxUserTags endpoints to read nickname, phone, unionid and tags, and add or remove fan tags.
References6
- github.com/niefy/wx-api/blob/0.8.2/src/main/java/com/github/nie…
- github.com/niefy/wx-api/blob/0.8.2/src/main/java/com/github/nie…
- github.com/niefy/wx-api/blob/0.8.2/src/main/java/com/github/nie…
- hackmd.io/@hieuPenguinnn/wx-api-cross-tenant-idor-and-unauth-fa…
- www.vulncheck.com/advisories/niefy-wx-api-through-0.8.2-authent…
- hackmd.io/@hieuPenguinnn/wx-api-cross-tenant-idor-and-unauth-fa…
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - CVSS 4.0
-
6.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 36 · as of 10 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.