Vulnerability in Kernel (CVE-2023-53728)

Summary

Vulnerability in Kernel (CVE-2023-53728). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7 or later.

Original description

The description as published by the source.

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

posix-timers: Ensure timer ID search-loop limit is valid

posix_timer_add() tries to allocate a posix timer ID by starting from the
cached ID which was stored by the last successful allocation.

This is done in a loop searching the ID space for a free slot one by
one. The loop has to terminate when the search wrapped around to the
starting point.

But that's racy vs. establishing the starting point. That is read out
lockless, which leads to the following problem:

CPU0 CPU1
posix_timer_add()
start = sig->posix_timer_id;
lock(hash_lock);
... posix_timer_add()
if (++sig->posix_timer_id < 0)
start = sig->posix_timer_id;
sig->posix_timer_id = 0;

So CPU1 can observe a negative start value, i.e. -1, and the loop break
never happens because the condition can never be true:

if (sig->posix_timer_id == start)
break;

While this is unlikely to ever turn into an endless loop as the ID space is
huge (INT_MAX), the racy read of the start value caught the attention of
KCSAN and Dmitry unearthed that incorrectness.

Rewrite it so that all id operations are under the hash lock.

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-2023-53728 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7 or later.
If unsure, ask your IT team or search "Kernel CVE-2023-53728" on the vendor's site.

CVE-2023-53728 (Kernel)
Patched: 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7 — 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.

❓ 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 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7.

🛡️ 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 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7
```
ステージング環境で 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.150, 6.1.107, 6.4.7 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。
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":"3.10.0"},{"fixed":"4.14.322"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"4.19.291"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.251"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.150"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.107"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.4.7"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

Debian DEBIAN-CVE-2023-53728 linux Fixed in: 5.10.191-1
Ubuntu UBUNTU-CVE-2023-53728 linux