Vulnerability in HyperKit (CVE-2021-32845)
Summary
Vulnerability in HyperKit (CVE-2021-32845). Successful exploitation can lead to full system takeover. Exploitable via qnotify.
Original description
The description as published by the source.
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-32845 has been found in HyperKit.
Attackers can target a specific entry point like qnotify over the network to misuse the product.
Successful exploitation can lead to full system takeover.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "HyperKit CVE-2021-32845" on the vendor's site.
CVE-2021-32845 (HyperKit)
Attack vector: local / no user interaction
Attack surface: qnotify / pci_vtrnd_notify / vq_getchain
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in HyperKit. Attackers reach the vulnerable code path via qnotify.
Check the vendor advisory for the affected versions of HyperKit. Attack surface: qnotify / pci_vtrnd_notify / vq_getchain.
Severity: ?. Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'HyperKit' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'HyperKit' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
HyperKitを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- advisory securitylab.github.com
- patch github.com
- patch github.com