CVE-2026-88010

Description

Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.7.13, checkPassword in pkg/middlewares/auth/basic_auth.go constructs the BasicAuth singleflight key from the submitted password and stored secret. Concurrent requests for absent usernames therefore coalesce on one key while configured usernames perform separate password hashes, creating an unauthenticated timing discrepancy that reveals whether a username exists. Sequential checks remain cost-equalized, Traefik v2 and Digest authentication are not affected, and the issue does not disclose credentials or bypass authentication. This issue is fixed in version 3.7.13.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: MEDIUM
CVSS score: 6.3 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Effective score: 6.3 / 10 MEDIUM source: CNA overview
CWE(s): CWE-208
Reserved: 2026-09-09
Published: 2026-09-22 15:38 UTC
Last updated: 2026-09-22 16:00 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/88xxx/CVE-2026-88010.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: 2026-09-22 16:18:06 UTC
NVD last modified: 2026-09-22 16:18:06 UTC

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-2026-84532
Assigner: GitHub_M
Published: Sep 22, 2026, 3:38:25 PM
Updated: Sep 22, 2026, 4:00:11 PM
EUVD base score (CVSS 4.0): 6.3 / 10
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
EUVD-reported EPSS: 0.0000
Vendors: traefik
Products: traefik (3.6.11, < 3.7.13)
Aliases: GHSA-8fcf-v89g-xpg6

ENISA description: Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.7.13, checkPassword in pkg/middlewares/auth/basic_auth.go constructs the BasicAuth singleflight key from the submitted password and stored secret. Concurrent requests for absent usernames therefore coalesce on one key while configured usernames perform separate password hashes, creating an unauthenticated timing discrepancy that reveals whether a username exists. Sequential checks remain cost-equalized, Traefik v2 and Digest authentication are not affected, and the issue does not disclose credentials or bypass authentication. This issue is fixed in version 3.7.13.

EUVD references (4)

Affected products (1)

Vendor	Product	Versions	Platforms
traefik	traefik	`>= 3.6.11, < 3.7.13` (affected)	—

Vendor references (4)

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

https://github.com/traefik/traefik/security/advisories/GHSA-8fcf-v89g-xpg6 x_refsource_CONFIRM
https://github.com/traefik/traefik/pull/13816 x_refsource_MISC
https://github.com/traefik/traefik/commit/ddc1bf4660b85fd61fafdd821eb8216fb1a0b130 x_refsource_MISC
https://github.com/traefik/traefik/releases/tag/v3.7.13 x_refsource_MISC

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 (4)

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://github.com/traefik/traefik/commit/ddc1bf4660b85fd61fafdd821eb8216fb1a0b130 security-advisories@github.com
https://github.com/traefik/traefik/pull/13816 security-advisories@github.com
https://github.com/traefik/traefik/releases/tag/v3.7.13 security-advisories@github.com
https://github.com/traefik/traefik/security/advisories/GHSA-8fcf-v89g-xpg6 security-advisories@github.com

Remediations (10)

Security Advisory - Action Required - Active Exploitation of CVE-2026 ...

web:blog.checkpoint.com

CVE - 2026 -93616 is a newly discovered zero-day vulnerability in Security Management, and a fix is available now as part of this advisory. Fixes are available for both vulnerabilities. Customers running affected versions should install the applicable fixes immediately. Affected versions and remediation instructions are detailed below.

2026-09-23 15:42 UTC
Microsoft's September 2026 Patch Tuesday addresses 964 CVEs (CVE-2026 ...

web:connect.tenable.com

On September 8, Microsoft released its September 2026 Patch Tuesday release which patched 964 CVEs with 104 rated critical and 860 rated as important. This update includes patches for two zero-days that were exploited in the wild.

2026-09-23 15:42 UTC
Security Update Guide - Microsoft

web:msrc.microsoft.com

The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.

2026-09-23 15:42 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-23 15:42 UTC
August 2026 CVE Advisory Notification - Security

web:support.servicenow.com

Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity

2026-09-23 15:42 UTC
Patch Tuesday Vulnerability Insights - Action1

web:www.action1.com

Patch Tuesday is a scheduled release day for software patches, primarily used by Microsoft, to fix security vulnerabilities, bugs, and performance issues in its software products like Windows, Office, and Azure. It occurs monthly and aims to standardize the process of delivering security updates to ensure devices remain protected.

2026-09-23 15:42 UTC
CVE-2026-88010: traefik: Traefik is an open source HTTP ... - Rapid7

web:www.rapid7.com

CVE-2026-88010 : traefik: Traefik is an open source HTTP reverse proxy and load balancer. View severity, references, and remediation details from Rapid7.

2026-09-23 15:42 UTC
Microsoft Patches Record 974 Vulnerabilities, Including Two Exploited ...

web:www.securityweek.com

Microsoft on Tuesday rolled out a record number of patches, fixing 974 CVEs across its products, including two vulnerabilities exploited in the wild as zero-days. The first exploited zero-day, CVE - 2026 -85880, is a heap buffer overflow issue in the Windows Advanced Local Procedure Call (ALPC) that could allow a local attacker to gain System privileges. "An attacker who can execute code in a ...

2026-09-23 15:42 UTC
September 2026 Microsoft Patch Tuesday | Tenable®

web:www.tenable.com

Microsoft patched 964 CVEs in September, the most ever in a Patch Tuesday release in its history, including two zero-day vulnerabilities exploited in the wild.

2026-09-23 15:42 UTC
Patch Tuesday September 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-09-23 15:42 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-88010.json.

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                "id": "CVE-2026-88010",
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                    "Automatable": "no"
                  },
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                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-22T15:59:02.259376Z",
                "version": "2.0.3"
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          "value": "Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.7.13, checkPassword in pkg/middlewares/auth/basic_auth.go constructs the BasicAuth singleflight key from the submitted password and stored secret. Concurrent requests for absent usernames therefore coalesce on one key while configured usernames perform separate password hashes, creating an unauthenticated timing discrepancy that reveals whether a username exists. Sequential checks remain cost-equalized, Traefik v2 and Digest authentication are not affected, and the issue does not disclose credentials or bypass authentication. This issue is fixed in version 3.7.13."
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        "advisory": "GHSA-8fcf-v89g-xpg6",
        "discovery": "UNKNOWN"
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      "title": "Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle"
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