CVE-2024-45410: HTTP client can manipulate custom HTTP headers that are added by Traefik

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 1.5%, percentile 74: FIRST’s model estimates a 1.5% chance of exploitation activity in the next 30 days, higher than 74% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes github.com/traefik/traefik/v3 (Go) >= 3.0.0-beta3, < 3.1.3, fixed in 3.1.3; github.com/traefik/traefik/v2 (Go) < 2.11.9, fixed in 2.11.9; github.com/traefik/traefik (Go) < 2.11.9, fixed in 2.11.9. Check your lockfile, including transitive dependencies.

What it is

Traefik is a golang, Cloud Native Application Proxy. When a HTTP request is processed by Traefik, certain HTTP headers such as X-Forwarded-Host or X-Forwarded-Port are added by Traefik before the request is routed to the application. For a HTTP client, it should not be possible to remove or modify these headers. Since the application trusts the value of these headers, security implications might arise, if they can be modified. For HTTP/1.1, however, it was found that some of theses custom headers can indeed be removed and in certain cases manipulated. The attack relies on the HTTP/1.1 behavior, that headers can be defined as hop-by-hop via the HTTP Connection header. This issue has been addressed in release versions 2.11.9 and 3.1.3. Users are advised to upgrade. There are no known workarounds for this vulnerability.

From the GitHub advisory

Impact

There is a vulnerability in Traefik that allows the client to remove the X-Forwarded headers (except the header X-Forwarded-For).

Patches

- https://github.com/traefik/traefik/releases/tag/v2.11.9 - https://github.com/traefik/traefik/releases/tag/v3.1.3

Workarounds

Weakness type: CWE-345, CWE-348.

Product: github.com/traefik/traefik/v3 (Go) · Assigned by: GitHub_M · Published: 2024-09-19

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: none (no login)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 1.51% probability of exploitation activity in the next 30 days; percentile 74.

Timeline

• 2024-09-19 — CVE record published by GitHub_M
• 2024-09-19 — GitHub-reviewed advisory GHSA-62c8-mh53-4cqv published (critical)
• 2024-09-20 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-62c8-mh53-4cqv github.com
2. CVE.org record CVE-2024-45410 cve.org
3. NVD entry CVE-2024-45410 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com
4. github.com github.com

Critical Go advisories · Today’s Security Digest