Vulnerability in Prometheus
CVE-2026-119566
Prometheus through 3.15.1 contains a credential leak vulnerability that allows attackers to capture Azure AD or Google IAM bearer tokens by redirecting remote_write requests to another host. Attackers controlling the remote-write endpoint or a redirecting server can return a 3xx to their host and replay the token, for example to write metrics to the victim's backend.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/prometheus/prometheus/blob/v3.15.1/storage/remote/azuread/azuread.go (technical-description)
- github.com/prometheus/prometheus/blob/v3.15.1/storage/remote/client.go (technical-description)
- github.com/prometheus/common/pull/901 (issue-tracking, related, patch)
- abraxaslabs.tech/research/prometheus-bearer-redirect (third-party-advisory)
- github.com/prometheus/prometheus (product)
- www.vulncheck.com/advisories/prometheus-through-3.15.1-credential-leak-via-remo… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-119566?
- CVE-2026-119566 is a medium-severity vulnerability in Prometheus, classified under Insufficiently Protected Credentials. CVSS score: 4.8/10. Published 2026-10-30.
- How severe is CVE-2026-119566?
- Medium severity. CVSS v3 base score is 4.8 out of 10.