Security readout for executives and security teams
Plain-English summary
Elastic APM .NET Agent could expose sensitive HTTP header values in APM data when an application error occurs. The issue is low severity because exploitation requires adjacent access, high privileges, and user interaction, and only confidentiality is affected.
Executive priority
Treat as a low-priority confidentiality issue unless affected services handle credentials, tokens, or regulated data in headers. Remediate through normal patch cycles and validate log exposure.
Technical view
CVE-2021-22143 is a CWE-200 information disclosure flaw in Elastic APM .NET Agent. Header sanitization normally protects sensitive HTTP headers before sending data to APM Server, but error handling could send unsanitized headers during application errors.
Likely exposure
Exposure is most likely where Elastic APM .NET Agent version 1.0.0 is deployed in .NET applications and error events include sensitive HTTP headers. The bundle does not prove other affected versions.
Exploitation context
The source bundle does not report active exploitation, and the CVE is not listed as KEV. CVSS indicates adjacent access, high privileges, and user interaction are required, limiting practical exploitability.
Researcher notes
The key behavior is a failure path in header sanitization during application errors. Evidence is limited to the CVE description and Elastic references; do not assume exploit availability, broader version ranges, or a specific fix beyond vendor guidance.
Mitigation direction
- Check Elastic's security update for the fixed or recommended agent version.
- Upgrade affected Elastic APM .NET Agent deployments per vendor guidance.
- Review application practices to avoid placing secrets in HTTP headers where possible.
- Restrict access to APM Server data and error logs containing request metadata.
Validation and detection
- Inventory .NET services using Elastic APM .NET Agent.
- Confirm deployed agent versions against Elastic's advisory and the CVE record.
- Review APM error events for sensitive HTTP headers captured during failures.
- Verify APM data access is limited to authorized operational staff.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-200: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-22143 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Low
- CVSS
- 2.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N0.71.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
2.1LowVector: CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://discuss.elastic.co/t/elastic-apm-net-agent-1-10-0-security-update/274668CVE reference
- https://www.elastic.co/community/securityCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Exposure of Sensitive Information to an Unauthorized Actor
Exposure of Sensitive Information to an Unauthorized Actor represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.