CVE-2026-88010: Traefik is an open source HTTP reverse proxy and load balancer

Routine

MEDIUM 5.3REMOTEUPGRADE

CVE-2026-88010 is a medium-severity flaw (CVSS 5.3) affecting traefik. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.3% (top 76%)
CISA exploited list	No
Weakness	CWE-208
Published	2026-09-22
Last modified	2026-10-29

Publisher (CNA): GitHub, Inc. · Vendor: traefik

Last updated 2026-10-29 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-09-22 16:18 UTCPublished CVE record published
2026-10-29 17:08 UTCUpdated Record last modified

traefik traefik UPGRADE

Affected: >= 3.6.11 and < 3.7.13

Fixed in: 3.7.13

Safe to downgrade to: a release before 3.6.11

1. Check installed version

apt-cache policy traefik || rpm -q traefik || traefik --version

2. UPGRADE to 3.7.13 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade traefik

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade traefik

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 3.6.11 (Debian / Ubuntu)

apt-cache madison traefik sudo apt install traefik=<VERSION_BEFORE_3.6.11> sudo apt-mark hold traefik

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list traefik sudo dnf downgrade traefik-<VERSION_BEFORE_3.6.11> sudo dnf versionlock add traefik

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-88010?

traefik: upgrade to 3.7.13. Exact commands for each OS are on this page.

Is CVE-2026-88010 being exploited?

CVE-2026-88010 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-88010 affect?

CVE-2026-88010 affects traefik. Severity is medium (CVSS 5.3). 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. Concurren

How urgent is CVE-2026-88010?

Priority 29/100. Remotely exploitable, no login, no user action

Software pages

Traefik vulnerabilities

Related CVEs

CVE-2026-114656 HIGH 7.5 UPGRADE Traefik before 2.11.58 and 3.7.13 contains an authentication bypass vulnerability that allows unauthenticated
CVE-2026-114641 LOW 3.7 UPGRADE Traefik 2.11.x before 2.11.58 and 3.x before 3.7.14 contains a race condition in NTLM and Kerberos (Negotiate)
CVE-2026-114637 HIGH 8.7 UPGRADE Traefik from v3.2.0 before v3.7.14 contains an authentication bypass vulnerability in the experimental FastPro
CVE-2026-114640 HIGH 8.7 UPGRADE Traefik from v3.7.0 before v3.7.14 contains an authentication bypass vulnerability in its Kubernetes Ingress-N
CVE-2026-114636 HIGH 8.7 DOWNGRADE Traefik v3.7.13 before v3.7.14 contains an access-control bypass in the Kubernetes Ingress NGINX provider, whe

References

← Back to latest CVEs