Answer in brief
CVE-2026-98851 records a Unknown severity vulnerability in netfilter: nft_flow_offload: drop flowtable reference on init error path. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. 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), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | 4.16 | Not reported |
| Linux/Linuxgeneric | >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <64ac0cb574c740bf723affb79b646eeba920db6b || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <c5f91098edee98c015f78488460a0609e62582a5 || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <4cd378423a33194a773c267fc58606d28fce95cf || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <747928b5d4ff8c8de55138a54c13980e4bb88578 | 64ac0cb574c740bf723affb79b646eeba920db6b, c5f91098edee98c015f78488460a0609e62582a5, 4cd378423a33194a773c267fc58606d28fce95cf, 747928b5d4ff8c8de55138a54c13980e4bb88578 |
| Linux/Linuxgeneric | >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <1d27214fd9a4d2c0c6d998fc9d4fb61448a3438e || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <64ac0cb574c740bf723affb79b646eeba920db6b || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <c5f91098edee98c015f78488460a0609e62582a5 || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <4cd378423a33194a773c267fc58606d28fce95cf || >=a3c90f7a2323b331ae816d5b0633e68148e25d04 <747928b5d4ff8c8de55138a54c13980e4bb88578 | 1d27214fd9a4d2c0c6d998fc9d4fb61448a3438e, 64ac0cb574c740bf723affb79b646eeba920db6b, c5f91098edee98c015f78488460a0609e62582a5, 4cd378423a33194a773c267fc58606d28fce95cf, 747928b5d4ff8c8de55138a54c13980e4bb88578 |
Published upstream
Oct 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 18, 2026
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_flow_offload: drop flowtable reference on init error path nft_flow_offload_init() bumps the flowtable use count with nft_use_inc() before calling nf_ct_netns_get(). When the latter fails, the error is returned as-is and the reference is leaked. The upper layers do not balance it either: nf_tables_newexpr() clears expr->ops when the expression init callback fails, so the nft_expr_more() iteration in nft_rule_expr_deactivate() and nf_tables_rule_destroy() stops right before the failed expression and its ->destroy callback, which would drop the reference, never runs. Each failed rule addition therefore leaks one flowtable reference and the flowtable can no longer be removed: NFT_MSG_DELFLOWTABLE keeps reporting -EBUSY even though no rule references it. Save the nf_ct_netns_get() return value and undo the nft_use_inc() when it fails, restoring the inc/dec pairing within nft_flow_offload_init() itself.
Quoted source text, attributed separately from HOL analysis.