CVE-2026-88837

Description

BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the authentication check.

Overview

State: PUBLISHED
Assigner (CNA): redhat
CVSS severity: MEDIUM
CVSS score: 6.5 / 10
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Effective score: 6.5 / 10 MEDIUM source: CNA overview
CWE(s): CWE-305
Reserved: 2026-09-10
Published: 2026-09-23 17:45 UTC
Last updated: 2026-09-23 18:00 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/88xxx/CVE-2026-88837.json

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-23 18:17:10 UTC
NVD last modified: 2026-09-23 19:19:42 UTC
NVD CVSS v3.1: 6.5 / 10 MEDIUM source: secalert@redhat.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Exploitability subscore: 2.2 / 10
Impact subscore: 4.2 / 10

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85511
Assigner: redhat
Published: Sep 23, 2026, 5:45:31 PM
Updated: Sep 23, 2026, 6:00:58 PM
EUVD base score (CVSS 3.1): 6.5 / 10
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
EUVD-reported EPSS: 0.0000
Aliases: GHSA-f9qv-fq2p-pvch

ENISA description: BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the authentication check.

EUVD references (2)

Affected products (1)

Vendor	Product	Versions	Platforms
Red Hat	Red Hat Hardened Images	—	—

Vendor references (2)

References embedded in the original CVE record by the assigning CNA.

https://access.redhat.com/security/cve/CVE-2026-88837 vdb-entryx_refsource_REDHAT
RHBZ#2531351 issue-trackingx_refsource_REDHAT

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://access.redhat.com/security/cve/CVE-2026-88837 secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2531351 secalert@redhat.com

Remediations (10)

CVE-2026-88837 - Red Hat Customer Portal

web:access.redhat.com

Overall, you have the following options: Upgrade to a supported product version that includes a fix for this vulnerability (recommended). Apply a mitigation (if one exists). Customers with the Technical Account Manager (TAM) RHEL Security Select Add-on can review this CVE directly with their TAM.

2026-09-24 11:47 UTC
Security Updates - Red Hat Customer Portal

web:access.redhat.com

Products & tools Red Hat Documentation Find answers, get guidance, and learn how to use Red Hat products. Red Hat Ecosystem Catalog Find hardware, software, and cloud providers―and download container images―certified to perform with Red Hat technologies.

2026-09-24 11:47 UTC
CVE-2026-88837 - Busybox: busybox: httpd misidentifies yescrypt ...

web:cvefeed.io

The following list is the news that have been mention CVE-2026-88837 vulnerability anywhere in the article. Results are limited to the first 20 news articles due to potential performance issues. The following table lists the changes that have been made to the CVE-2026-88837 vulnerability over time.

2026-09-24 11:47 UTC
CVE-2026-88837 - Exploits & Severity - Feedly

web:feedly.com

Sep 23, 2026 at 10:50 AM / Radar - Latest Security Threats Vendor advisory RedHat CVE advisory released a security advisory ( CVE-2026-88837 ).

2026-09-24 11:47 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-24 11:47 UTC
CVE-2026-88837 - vulnerability database | Vulners.com

web:vulners.com

This candidate has been reserved by an organization or individual " "that will use it when announcing a new security problem. When the candidate has been " "publicized, the details for this candidate will be provided.

2026-09-24 11:47 UTC
Critical Patches Issued for Microsoft Products, August 11, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-09-24 11:47 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:47 UTC
CVE-2026-88837: Red Hat Red Hat Hardened Images: BusyBox httpd ... - Rapid7

web:www.rapid7.com

CVE-2026-88837 : Red Hat Red Hat Hardened Images: BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the…. View severity, references, and remediation details from Rapid7.

2026-09-24 11:47 UTC
CVE-2026-88837 | Tenable®

web:www.tenable.com

BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the authentication check.

2026-09-24 11:47 UTC

AI Forensic Analysis

Only Available for Registered Users. Sign in to view.

Raw JSON

The full cvelistV5 record. Download as CVE-2026-88837.json.

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-88837",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-23T18:00:23.871775Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-23T18:00:58.072Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:hummingbird:1"
          ],
          "defaultStatus": "affected",
          "packageName": "busybox",
          "product": "Red Hat Hardened Images",
          "vendor": "Red Hat"
        }
      ],
      "datePublic": "2026-09-23T16:35:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "BusyBox httpd treats yescrypt ($y$) password hashes as plaintext during Basic Authentication, inverting the authentication check."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-305",
              "description": "Authentication Bypass by Primary Weakness",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-23T17:45:31.496Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-88837"
        },
        {
          "name": "RHBZ#2531351",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531351"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-09-09T00:00:00.000Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2026-09-23T16:35:00.000Z",
          "value": "Made public."
        }
      ],
      "title": "Busybox: busybox: httpd misidentifies yescrypt password hashes as plaintext, inverting authentication",
      "workarounds": [
        {
          "lang": "en",
          "value": "Do not use BusyBox httpd for password-protected resources. If it must be used, configure authentication with SHA-512 ($6$) hashes, which are correctly detected. Upstream should update the hash detection logic to recognize the $y$ prefix."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-305: Authentication Bypass by Primary Weakness"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-88837",
    "datePublished": "2026-09-23T17:45:31.496Z",
    "dateReserved": "2026-09-10T09:42:04.559Z",
    "dateUpdated": "2026-09-23T18:00:58.072Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}