---
id: CVE-2026-91995
title: >-
  pig before 4.1.0 contains an authentication bypass vulnerability in the
  /register/password endpoint where password verification results are discarded,
  allowing any value as the current password
summary: >-
  pig before 4.1.0 contains an authentication bypass vulnerability in the
  /register/password endpoint where password verification results are discarded,
  allowing any value as the current password. Remote attackers can submit a
  username wit…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-620
vendor: pig-mesh
product: pig
affected:
  - pig < 4.1.0
published: '2026-09-15'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T18:18:06.243'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91995'
references:
  - url: 'https://github.com/geo-chen/oss/blob/main/pig.md'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/pig-mesh/pig'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/pig-mesh/pig/blob/v4.0.0/pig-upms/pig-upms-biz/src/main/java/com/pig4cloud/pig/admin/controller/SysRegisterController.java#L21-L53
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/pig-mesh/pig/blob/v4.0.0/pig-upms/pig-upms-biz/src/main/java/com/pig4cloud/pig/admin/service/impl/SysUserServiceImpl.java#L650-L669
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/pig-mesh/pig/commit/ce958668f399110b97b3f1fcc5f517ff9bcfd535
    label: disclosure@vulncheck.com
  - url: 'https://github.com/pig-mesh/pig/issues/1249'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/pig-before-4.1.0-unverified-password-change-via-register-password
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
epss: 0.00608
epssPercentile: 0.47487
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-18T17:15:18.219296Z'
ingestedAt: '2026-09-15T12:36:50.173Z'
---

## Overview

pig before 4.1.0 contains an authentication bypass vulnerability in the /register/password endpoint where password verification results are discarded, allowing any value as the current password. Remote attackers can submit a username with an incorrect current password to overwrite any account credential including the admin account and gain full administrative control.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.