Answer in brief
CVE-2026-46101 records a Medium severity (CVSS 5.5) vulnerability in netfilter: reject zero shift in nft_bitwise. 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 1518F-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 5.5. 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 1518F-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <9baa08d6b6b096fad70049533f0d705d85fdc979 || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <4fccea585631621c975883911a08d15b6671f7dc || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <9ad26c272405f53834871cc2e46b9b5393a666c3 || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <bffef0acec9c3b837a785248a893137fb7f26c95 || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <ca24f1243ad1a4d12d6a23876bbbe3ed02099853 || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <6f820139d16a4c9865a145d4a9cf9c92cc632c14 || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <f370205974f171a5868c13ff30d7642fed46e47b || >=567d746b55bc66d3800c9ae91d50f0c5deb2fd93 <fe11e5c40817b84abaa5d83bfb6586d8412bfd07 | 9baa08d6b6b096fad70049533f0d705d85fdc979, 4fccea585631621c975883911a08d15b6671f7dc, 9ad26c272405f53834871cc2e46b9b5393a666c3, bffef0acec9c3b837a785248a893137fb7f26c95, ca24f1243ad1a4d12d6a23876bbbe3ed02099853, 6f820139d16a4c9865a145d4a9cf9c92cc632c14, f370205974f171a5868c13ff30d7642fed46e47b, fe11e5c40817b84abaa5d83bfb6586d8412bfd07 |
| Linux/Linuxgeneric | 5.6 | Not reported |
| Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
| Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric | >=V3.1.6 <* | * |
Published upstream
May 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
In the Linux kernel, the following vulnerability has been resolved: netfilter: reject zero shift in nft_bitwise Reject zero shift operands for nft_bitwise left and right shift expressions during initialization. The carry propagation logic computes the carry from the adjacent 32-bit word using BITS_PER_TYPE(u32) - shift. A zero shift operand turns this into a 32-bit shift, which is undefined behaviour. Reject zero shift operands in the control plane, alongside the existing check for values greater than or equal to 32, so malformed rules never reach the packet path.
Quoted source text, attributed separately from HOL analysis.