Vulnerability in Kernel (CVE-2024-35981)
Summary
Vulnerability in Kernel (CVE-2024-35981). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.1.90, 6.6.29, 6.8.7 or later.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
virtio_net: Do not send RSS key if it is not supported
There is a bug when setting the RSS options in virtio_net that can break
the whole machine, getting the kernel into an infinite loop.
Running the following command in any QEMU virtual machine with virtionet
will reproduce this problem:
# ethtool -X eth0 hfunc toeplitz
This is how the problem happens:
-
ethtool_set_rxfh() calls virtnet_set_rxfh()
-
virtnet_set_rxfh() calls virtnet_commit_rss_command()
-
virtnet_commit_rss_command() populates 4 entries for the rss
scatter-gather -
Since the command above does not have a key, then the last
scatter-gatter entry will be zeroed, since rss_key_size == 0.
sg_buf_size = vi->rss_key_size; -
This buffer is passed to qemu, but qemu is not happy with a buffer
with zero length, and do the following in virtqueue_map_desc() (QEMU
function):
if (!sz) {
virtio_error(vdev, "virtio: zero sized buffers are not allowed");
-
virtio_error() (also QEMU function) set the device as broken
vdev->broken = true;
-
Qemu bails out, and do not repond this crazy kernel.
-
The kernel is waiting for the response to come back (function
virtnet_send_command()) -
The kernel is waiting doing the following :
while (!virtqueue_get_buf(vi->cvq, &tmp) &&
!virtqueue_is_broken(vi->cvq))
cpu_relax(); -
None of the following functions above is true, thus, the kernel
loops here forever. Ke…
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-2024-35981 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.1.90, 6.6.29, 6.8.7 or later.
If unsure, ask your IT team or search "Kernel CVE-2024-35981" on the vendor's site.
CVE-2024-35981 (Kernel)
Patched: 6.1.90, 6.6.29, 6.8.7 — apply immediately
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 Kernel.
Check the vendor advisory for the affected versions of Kernel.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 6.1.90, 6.6.29, 6.8.7.
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 'Kernel' . 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 'Kernel' . | 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
Kernelを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade Kernel to 6.1.90, 6.6.29, 6.8.7ステージング環境で 6.1.90, 6.6.29, 6.8.7 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2024-35981 linux Fixed in: 6.1.90-1
References
- advisory github.com
- advisory nvd.nist.gov
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org