Vulnerability in Linux kernel
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-2022-49340 has been found in Linux kernel.
Confidential information can be exposed externally. CVSS score: 7.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2022-49340" on the vendor's site.
CVE-2022-49340 (Linux kernel) — CVSS v3 7.1
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.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.1/10). Confidential information can be exposed externally.
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
-
1
Identify exposureidentify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2
Post-deployment verificationverify
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
| Ecosystem | Package | Affected | Fixed |
|---|---|---|---|
| Linux | Kernel |
< 4.19.247 ≥ 4.20.0, < 5.4.198 ≥ 5.5.0, < 5.10.122 ≥ 5.11.0, < 5.15.47 ≥ 5.15.0, < 5.17.15 ≥ 5.16.0, < 5.18.4 |
4.19.247 5.4.198 5.10.122 5.15.47 5.17.15 5.18.4 |
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2022-49340 linux Fixed in: 5.10.127-1
- Ubuntu UBUNTU-CVE-2022-49340 linux-azure Fixed in: 4.15.0-1150.165~14.04.1
Original description The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
ip_gre: test csum_start instead of transport header
GRE with TUNNEL_CSUM will apply local checksum offload on
CHECKSUM_PARTIAL packets.
ipgre_xmit must validate csum_start after an optional skb_pull,
else lco_csum may trigger an overflow. The original check was
if (csum && skb_checksum_start(skb) < skb->data)
return -EINVAL;
This had false positives when skb_checksum_start is undefined:
when ip_summed is not CHECKSUM_PARTIAL. A discussed refinement
was straightforward
if (csum && skb->ip_summed == CHECKSUM_PARTIAL &&
skb_checksum_start(skb) < skb->data)
return -EINVAL;
But was eventually revised more thoroughly:
- restrict the check to the only branch where needed, in an
uncommon GRE path that uses header_ops and calls skb_pull. - test skb_transport_header, which is set along with csum_start
in skb_partial_csum_set in the normal header_ops datapath.
Turns out skbs can arrive in this branch without the transport
header set, e.g., through BPF redirection.
Revise the check back to check csum_start directly, and only if
CHECKSUM_PARTIAL. Do leave the check in the updated location.
Check field regardless of whether TUNNEL_CSUM is configured.
Source: NIST National Vulnerability Database NVD
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
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org