Vulnerability · CVE-2026-26998
Traefik is an HTTP reverse proxy and load balancer.
Published Mar 5, 2026 · catalog updated Jun 17, 2026 · Traefik is an HTTP
Check if you run it
No confirmed exploitation is on record for CVE-2026-26998. EPSS is 0.57%. Act only if a listed version of Traefik is an HTTP is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (Traefik is an HTTP).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium4.4
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.57%
- Remediation
- Advisory link
- Affected products
- cpe traefik/traefik
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing the ForwardAuth middleware responses. When Traefik is configured to use the ForwardAuth middleware, the response body from the authentication server is read entirely into memory without any size limit. There is no maxResponseBodySize configuration to restrict the amount of data read from the authentication server response. If the authentication server returns an unexpectedly large or unbounded response body, Traefik will allocate unlimited memory, potentially causing an out-of-memory (OOM) condition that crashes the process. This results in a denial of service for all routes served by the affected Traefik instance. This issue has been patched in versions 2.11.38 and 3.6.9.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe traefik/traefikversion unspecified
How to fix CVE-2026-26998
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-26998. EPSS is 0.57%. Act only if a listed version of Traefik is an HTTP is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-770: Allocation of Resources Without Limits or Throttling. EPSS 0.57%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Mar 5, 2026 · NIST NVD
Detected
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing the ForwardAuth middleware responses. When Traefik is configured to use the ForwardAuth middleware, the response body from the authentication server is read entirely into memory without any size limit. There is no maxResponseBodySize configuration to restr
Jun 17, 2026 · NIST NVD
Updated
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing the ForwardAuth middleware responses. When Traefik is configured to use the ForwardAuth middleware, the response body from the authentication server is read entirely into memory without any size limit. There is no maxResponseBodySize configuration to restr
Sources
- CVE.orgVulnerability recordCVE-2026-26998
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-26998
30-day exploitation probability 0.6%
first.org - NIST NVDVulnerability recordCVE-2026-26998
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing the ForwardAuth middleware responses. When Traefik is configured to use the ForwardAuth middleware, the response body from the authentic
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.