CVE-2021-37705
No exploitation reported by the sources we read.
- Published2021-08-13
- Fixed in2.31.0
- WeaknessCWE-285 · CWE-346 · CWE-863
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
OneFuzz is an open source self-hosted Fuzzing-As-A-Service platform. Starting with OneFuzz 2.12.0 or greater, an incomplete authorization check allows an authenticated user from any Azure Active Directory tenant to make authorized API calls to a vulnerable OneFuzz instance. To be vulnerable, a OneFuzz deployment must be both version 2.12.0 or greater and deployed with the non-default --multi_tenant_domain option. This can result in read/write access to private data such as software vulnerability and crash information, security testing tools and proprietary code and symbols. Via authorized API calls, this also enables tampering with existing data and unauthorized code execution on Azure compute resources. This issue is resolved starting in release 2.31.0, via the addition of application-level check of the bearer token's `issuer` against an administrator-configured allowlist. As a workaround users can restrict access to the tenant of a deployed OneFuzz instance < 2.31.0 by redeploying in the default configuration, which omits the `--multi_tenant_domain` option.
Timeline
dates in UTC- 2021-08-1321:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-37705?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-37705?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 2.x | ≥ 2.12.0, < 2.31.0 | 2.31.0 | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Microsoft onefuzz to 2.31.0
Advisories and patches
- github.comPatch
- github.comPatch
- github.comRelease Notes
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- Published
- 2021-08-13
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-37705?
Is CVE-2021-37705 actively exploited?
What is the CVSS score for CVE-2021-37705?
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