Vulnerability in Kernel (CVE-2023-54195)

Summary

Vulnerability in Kernel (CVE-2023-54195). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.2.16, 6.3.3 or later.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

rxrpc: Fix timeout of a call that hasn't yet been granted a channel

afs_make_call() calls rxrpc_kernel_begin_call() to begin a call (which may
get stalled in the background waiting for a connection to become
available); it then calls rxrpc_kernel_set_max_life() to set the timeouts -
but that starts the call timer so the call timer might then expire before
we get a connection assigned - leading to the following oops if the call
stalled:

BUG: kernel NULL pointer dereference, address: 0000000000000000
...
CPU: 1 PID: 5111 Comm: krxrpcio/0 Not tainted 6.3.0-rc7-build3+ #701
RIP: 0010:rxrpc_alloc_txbuf+0xc0/0x157
...
Call Trace:
 
 rxrpc_send_ACK+0x50/0x13b
 rxrpc_input_call_event+0x16a/0x67d
 rxrpc_io_thread+0x1b6/0x45f
 ? _raw_spin_unlock_irqrestore+0x1f/0x35
 ? rxrpc_input_packet+0x519/0x519
 kthread+0xe7/0xef
 ? kthread_complete_and_exit+0x1b/0x1b
 ret_from_fork+0x22/0x30

Fix this by noting the timeouts in struct rxrpc_call when the call is
created. The timer will be started when the first packet is transmitted.

It shouldn't be possible to trigger this directly from userspace through
AF_RXRPC as sendmsg() will return EBUSY if the call is in the
waiting-for-conn state if it dropped out of the wait due to a signal.

Source: OSV.dev (Open Source Vulnerabilities) NVD 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-2023-54195 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.2.16, 6.3.3 or later.
If unsure, ask your IT team or search "Kernel CVE-2023-54195" on the vendor's site.

CVE-2023-54195 (Kernel)
Patched: 6.2.16, 6.3.3 — 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.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 6.2.16, 6.3.3.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

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

1
Identify 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。
2
Apply patch patch
```
Upgrade Kernel to 6.2.16, 6.3.3
```
ステージング環境で 6.2.16, 6.3.3 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。
3
Post-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

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.2.16"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.3.0"},{"fixed":"6.3.3"}]}]