Answer in brief
CVE-2026-23231 records a High severity (CVSS 7.8) vulnerability in netfilter: nf_tables: fix use-after-free in nf_tables_addchain(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/RUGGEDCOM RST2428P (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-2026-23231 records a High severity (CVSS 7.8) vulnerability in netfilter: nf_tables: fix use-after-free in nf_tables_addchain(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/RUGGEDCOM RST2428P (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/RUGGEDCOM RST2428P (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 | >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <2a6586ecfa4ce1413daaafee250d2590e05f1a33 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <7017745068a9068904e1e7a1b170a5785647cc81 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <f3fe58ce37926a10115ede527d59b91bcc05400a || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <dbd0af8083dd201f07c49110b2ee93710abdff28 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <71e99ee20fc3f662555118cf1159443250647533 | 2a6586ecfa4ce1413daaafee250d2590e05f1a33, 7017745068a9068904e1e7a1b170a5785647cc81, f3fe58ce37926a10115ede527d59b91bcc05400a, dbd0af8083dd201f07c49110b2ee93710abdff28, 2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b, 71e99ee20fc3f662555118cf1159443250647533 |
| Linux/Linuxgeneric | 3.16 | Not reported |
| Siemens/RUGGEDCOM RST2428Pgeneric | >=0 <V4.0 | V4.0 |
| 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 4, 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: fix use-after-free in nf_tables_addchain() nf_tables_addchain() publishes the chain to table->chains via list_add_tail_rcu() (in nft_chain_add()) before registering hooks. If nf_tables_register_hook() then fails, the error path calls nft_chain_del() (list_del_rcu()) followed by nf_tables_chain_destroy() with no RCU grace period in between. This creates two use-after-free conditions: 1) Control-plane: nf_tables_dump_chains() traverses table->chains under rcu_read_lock(). A concurrent dump can still be walking the chain when the error path frees it. 2) Packet path: for NFPROTO_INET, nf_register_net_hook() briefly installs the IPv4 hook before IPv6 registration fails. Packets entering nft_do_chain() via the transient IPv4 hook can still be dereferencing chain->blob_gen_X when the error path frees the chain. Add synchronize_rcu() between nft_chain_del() and the chain destroy so that all RCU readers -- both dump threads and in-flight packet evaluation -- have finished before the chain is freed.
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/RUGGEDCOM RST2428P (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 | >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <2a6586ecfa4ce1413daaafee250d2590e05f1a33 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <7017745068a9068904e1e7a1b170a5785647cc81 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <f3fe58ce37926a10115ede527d59b91bcc05400a || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <dbd0af8083dd201f07c49110b2ee93710abdff28 || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b || >=91c7b38dc9f0de4f7f444b796d14476bc12df7bc <71e99ee20fc3f662555118cf1159443250647533 | 2a6586ecfa4ce1413daaafee250d2590e05f1a33, 7017745068a9068904e1e7a1b170a5785647cc81, f3fe58ce37926a10115ede527d59b91bcc05400a, dbd0af8083dd201f07c49110b2ee93710abdff28, 2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b, 71e99ee20fc3f662555118cf1159443250647533 |
| Linux/Linuxgeneric | 3.16 | Not reported |
| Siemens/RUGGEDCOM RST2428Pgeneric | >=0 <V4.0 | V4.0 |
| 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 4, 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: fix use-after-free in nf_tables_addchain() nf_tables_addchain() publishes the chain to table->chains via list_add_tail_rcu() (in nft_chain_add()) before registering hooks. If nf_tables_register_hook() then fails, the error path calls nft_chain_del() (list_del_rcu()) followed by nf_tables_chain_destroy() with no RCU grace period in between. This creates two use-after-free conditions: 1) Control-plane: nf_tables_dump_chains() traverses table->chains under rcu_read_lock(). A concurrent dump can still be walking the chain when the error path frees it. 2) Packet path: for NFPROTO_INET, nf_register_net_hook() briefly installs the IPv4 hook before IPv6 registration fails. Packets entering nft_do_chain() via the transient IPv4 hook can still be dereferencing chain->blob_gen_X when the error path frees the chain. Add synchronize_rcu() between nft_chain_del() and the chain destroy so that all RCU readers -- both dump threads and in-flight packet evaluation -- have finished before the chain is freed.
Quoted source text, attributed separately from HOL analysis.