CVE-2021-36157
Path traversal in Grafana Cortex
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.)
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
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.)
- Record
CVE-2021-36157- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-22
- Updated
- 2026-11-02
CVE List No score
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.)
- Record
CVE-2021-36157- Updated
- 2026-11-02
EUVDEUVD-2021-2088 No score
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.)
- Record
EUVD-2021-2088- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-jphm-g89m-v42p No score
Path traversal in Grafana Cortex
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.)
- Record
GHSA-jphm-g89m-v42p- Weakness
- CWE-22
- Updated
- 2026-11-02
OSV
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.)
- Record
CVE-2021-36157- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-jphm-g89m-v42p No score
Path traversal in Grafana Cortex
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.)
- Record
GHSA-jphm-g89m-v42p- Weakness
- CWE-22
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/cortexproject/cortexGo |
through 1.9.0 | None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-36157 is a medium vulnerability (CVSS 5.3) in Linuxfoundation Cortex, published August 3, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.39%, the 72nd percentile. No source names a fixed version.