# CVE-2026-90059: net: stmmac: restore NET_IP_ALIGN in the RX DMA offset > A misalignment in the stmmac network driver causes kernel panics on ARM32 systems when processing ICMP echo requests, leading to denial of service. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 17 Sep 2026 - **Updated:** 19 Oct 2026 - **Also known as:** BELL-CVE-2026-90059, DEBIAN-CVE-2026-90059, GHSA-j365-j246-5hmg, UBUNTU-CVE-2026-90059 ## What is CVE-2026-90059? CVE-2026-90059 is a high-severity denial of service vulnerability in Linux, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description In the Linux kernel, the following vulnerability has been resolved: net: stmmac: restore NET_IP_ALIGN in the RX DMA offset Since the RX path was converted to zero-copy, the page pool page is handed to the stack directly as the skb head, and the offset the DMA engine writes at is what determines the alignment of the packet headers. Before the conversion the payload was copied into an skb obtained from napi_alloc_skb(), which reserves NET_SKB_PAD + NET_IP_ALIGN. The conversion moved the headroom into stmmac_rx_offset() but did not carry over NET_IP_ALIGN, so on architectures where NET_IP_ALIGN is 2 the IP header now lands misaligned: 64 (NET_SKB_PAD) + 14 (ethernet) + 20 (IP) = 98 Same for the XDP branch: 256 (XDP_PACKET_HEADROOM) + 14 (ethernet) + 20 (IP) = 290 On ARM32 this is fatal, because ldm and ldrd trap on unaligned addresses even when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set. Any received echo request panics the machine, e.g: Unhandled fault: alignment exception (0x001) at 0x81873062 Internal error: : 1 [#1] SMP ARM Hardware name: Altera SOCFPGA Arria10 PC is at icmp_echo+0x38/0xa8 LR is at icmp_rcv+0x22c/0x370 Call trace: icmp_echo from icmp_rcv+0x22c/0x370 icmp_rcv from ip_protocol_deliver_rcu+0x2c/0x224 ip_protocol_deliver_rcu from ip_local_deliver+0xc8/0x1a0 ip_local_deliver from ip_sublist_rcv_finish+0x3c/0x50 ip_sublist_rcv_finish from ip_list_rcv_finish+0x110/0x118 ip_list_rcv_finish from ip_list_rcv+0xc8/0xdc ip_list_rcv from __netif_receive_skb_list_core+0x170/0x1c0 ... napi_complete_done from stmmac_napi_poll_rx+0xcb0/0x1030 Code: e24dd068 e59020a0 e28dc010 e0822001 (e8920003) Kernel panic - not syncing: Fatal exception in interrupt The faulting instruction is the ldm of *icmp_hdr(skb) in icmp_echo(). Fix by adding NET_IP_ALIGN back to the RX offset, which restores the alignment the stack used to get. Note that commit a955318fe67e ("stmmac: align RX buffers") made a similar change in 2021 and was reverted by commit 12d125b4574b ("stmmac: Revert "stmmac: align RX buffers"") because it caused packet corruption. That patch raised the offset from 0 without adjusting the buffer size accounting, so the DMA engine could arguably write past the end of the RX buffers, though this was never root caused. Commit df542f669307 ("net: stmmac: Switch to zero-copy in non-XDP RX path") since derives the page pool allocation from stmmac_rx_offset(), so the extra bytes are accounted for. ## Which versions are affected by CVE-2026-90059? ## How do I fix CVE-2026-90059? Apply the vendor's patch. ## Is CVE-2026-90059 being exploited? There is no known exploitation of CVE-2026-90059 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-90059 and fix it if it is affected. What it is: CVE-2026-90059 is a high-severity denial of service vulnerability in Linux, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-90059 in the wild and no public exploit code. Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-90059/ (Markdown: https://insights.sbomify.com/CVE-2026-90059/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90059 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90059 - OSV: https://osv.dev/vulnerability/CVE-2026-90059 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-90059/ Summaries are generated and may contain mistakes; the official description above is the record.