CVE-2021-36157

CVE-2021-36157 is a medium-severity vulnerability in Linuxfoundation Cortex with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Description

An issue was discovered in Grafana Cortex through 1.9.0. The header value X-Scope-OrgID is used to construct file paths for rules files, and if crafted to conduct directory traversal such as ae ../../sensitive/path/in/deployment pathname, then Cortex will attempt to parse a rules file at that location and include some of the contents in the error message. (Other Cortex API requests can also be sent a malicious OrgID header, e.g., tricking the ingester into writing metrics to a different location, but the effect is nuisance rather than information disclosure.)

Frequently asked questions

What is CVE-2021-36157?
An issue was discovered in Grafana Cortex through 1.9.0. The header value X-Scope-OrgID is used to construct file paths for rules files, and if crafted to conduct directory traversal such as ae ../../sensitive/path/in/deployment pathname, then Cortex will attempt to parse a rules file at that location and include some of the contents in the error message. (Other Cortex API requests can also be sent a malicious OrgID header, e.g., tricking the ingester into writing metrics to a different location, but the effect is nuisance rather than information disclosure.)
How severe is CVE-2021-36157?
CVE-2021-36157 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-36157 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36157?
CVE-2021-36157 affects Linuxfoundation Cortex. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36157?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36157 published?
CVE-2021-36157 was published on 2021-08-03 and last updated on 2026-06-17.

References

Affected products (1)

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