Use-After-Free in Linux kernel's netfilter (CVE-2023-3777)
Summary
Vulnerability in Linux kernel's netfilter (CVE-2023-3777). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation.
When nf_tables_delrule() is flushing table rules, it is not checked whether the chain is bound and the chain's owner rule can also release the objects in certain circumstances.
We recommend upgrading past commit 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
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-2023-3777 has been found in Linux kernel's netfilter.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel's netfilter CVE-2023-3777" on the vendor's site.
CVE-2023-3777 (Linux kernel's netfilter) — CWE-416 / CVSS v3 7.8
Attack vector: local / no user interaction
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.
Use-after-free (CWE-416) exists in Linux kernel's netfilter.
Check the vendor advisory for the affected versions of Linux kernel's netfilter.
Severity: High (CVSS 7.8/10). 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. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel's netfilter を使っているサービスとバージョンを洗い出す。
-
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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2023-3777 linux Fixed in: 5.10.191-1
- Ubuntu UBUNTU-CVE-2023-3777 linux-hwe-edge
References
- advisory packetstormsecurity.com
- advisory packetstormsecurity.com
- advisory github.com
- advisory debian.org
- patch kernel.dance
- patch git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web cert-portal.siemens.com
- web github.com