Answer in brief
CVE-2026-23392 records a High severity (CVSS 7.8) vulnerability in netfilter: nf_tables: release flowtable after rcu grace period on error. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-23392 records a High severity (CVSS 7.8) vulnerability in netfilter: nf_tables: release flowtable after rcu grace period on error. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <d2632de96ccb066e0131ad1494241b9c281c60b8 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <adee3436ccd29f1e514c028899e400cbc6d84065 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <7e3955b282eae20d61c75e499c75eade51c20060 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <c8092edb9a11f20f95ccceeb9422b7dd0df337bd || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <e78a2dcc7cfb87b64a631441ca7681492b347ef6 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <d73f4b53aaaea4c95f245e491aa5eeb8a21874ce | d2632de96ccb066e0131ad1494241b9c281c60b8, adee3436ccd29f1e514c028899e400cbc6d84065, 7e3955b282eae20d61c75e499c75eade51c20060, c8092edb9a11f20f95ccceeb9422b7dd0df337bd, e78a2dcc7cfb87b64a631441ca7681492b347ef6, d73f4b53aaaea4c95f245e491aa5eeb8a21874ce |
| Linux/Linuxgeneric | 4.16 | Not reported |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
Published upstream
Mar 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 14, 2026
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtable can be already registered, exposing this flowtable to packet path and nfnetlink_hook control plane. This error path is rare, it should only happen by reaching the maximum number hooks or by failing to set up to hardware offload, just call synchronize_rcu(). There is a check for already used device hooks by different flowtable that could result in EEXIST at this late stage. The hook parser can be updated to perform this check earlier to this error path really becomes rarely exercised. Uncovered by KASAN reported as use-after-free from nfnetlink_hook path when dumping hooks.
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <d2632de96ccb066e0131ad1494241b9c281c60b8 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <adee3436ccd29f1e514c028899e400cbc6d84065 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <7e3955b282eae20d61c75e499c75eade51c20060 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <c8092edb9a11f20f95ccceeb9422b7dd0df337bd || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <e78a2dcc7cfb87b64a631441ca7681492b347ef6 || >=3b49e2e94e6ebb8b23d0955d9e898254455734f8 <d73f4b53aaaea4c95f245e491aa5eeb8a21874ce | d2632de96ccb066e0131ad1494241b9c281c60b8, adee3436ccd29f1e514c028899e400cbc6d84065, 7e3955b282eae20d61c75e499c75eade51c20060, c8092edb9a11f20f95ccceeb9422b7dd0df337bd, e78a2dcc7cfb87b64a631441ca7681492b347ef6, d73f4b53aaaea4c95f245e491aa5eeb8a21874ce |
| Linux/Linuxgeneric | 4.16 | Not reported |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.5 <* | * |
Published upstream
Mar 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 14, 2026
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtable can be already registered, exposing this flowtable to packet path and nfnetlink_hook control plane. This error path is rare, it should only happen by reaching the maximum number hooks or by failing to set up to hardware offload, just call synchronize_rcu(). There is a check for already used device hooks by different flowtable that could result in EEXIST at this late stage. The hook parser can be updated to perform this check earlier to this error path really becomes rarely exercised. Uncovered by KASAN reported as use-after-free from nfnetlink_hook path when dumping hooks.
Quoted source text, attributed separately from HOL analysis.