--- schema: 1 kind: vulnerability title: "AMD-SB-7052 / CVE-2025-54518 — AMD Zen 2 µop-cache corruption / SoC isolation failure: local privilege escalation (CVSS 7.3), microcode mitigation in May 2026 Windows update and Xen XSA-490" headline: "AMD-SB-7052 / CVE-2025-54518 — AMD Zen 2 µop-cache corruption / SoC isolation failure: local privilege escalation (CVSS 7.3), microcode mitigation in May 2026" summary: "AMD disclosed AMD-SB-7052 (CVE-2025-54518, CVSS 7.3 on the CVSS 4.0 scale, CWE-1189 Improper Isolation of Shared Resources on System-on-Chip) affecting Zen 2-based processor models on 2026-05-12, with NCSC-NL flagging the advisory on 2026-05-15 (AMD Product Security, 2026-05-12 · NCSC-NL NCSC-2026-0158, 2026-05-15)." discovered_at: "2026-05-16T05:00:06Z" event_date: 2026-05-15 run_id: 2026-05-16-5bc123a0 priority: notable immediate_action: null tags: - vulnerabilities - lpe - patch-available regions: - global sectors: - technology - public-sector - education entities: - "trend:amd-sb-7052" cves: - id: CVE-2025-54518 cvss: "7.3" epss: null type: lpe vector: local auth: post-auth status: - patch-available sources: - url: "https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7052.html" publisher: "AMD Product Security AMD-SB-7052, 2026-05-12" role: primary - url: "https://advisories.ncsc.nl/advisory?id=NCSC-2026-0158" publisher: "NCSC-NL NCSC-2026-0158, 2026-05-15" role: corroborating closed_sources: [] evidence: [] verification: multi-source sourcing_note: null confidence: high update_of: null references: [] deep_dive: false deep_dive_category: null org_triage: null watchlist_hit: false actions: - "**Apply the May 2026 Microsoft Windows cumulative update — confirms AMD microcode mitigation for AMD-SB-7052 / CVE-2025-54518 is installed on Zen 2 hosts; apply Xen XSA-490 on bare-metal hypervisors.** Local privilege-escalation primitives with hypervisor-isolation implications matter for any multi-tenant context: VDI estates, university HPC clusters, cloud-hosted VMs on Zen 2 silicon. For Linux hypervisors apply distro kernel + microcode updates (Fedora has shipped corresponding bodhi updates per NCSC-NL CSAF); for Lenovo hardware consult Lenovo PSIRT for BIOS / UEFI guidance." migrated_from: briefs/2026-05-16.md --- AMD disclosed AMD-SB-7052 (CVE-2025-54518, CVSS 7.3 on the CVSS 4.0 scale, CWE-1189 Improper Isolation of Shared Resources on System-on-Chip) affecting Zen 2-based processor models on 2026-05-12, with NCSC-NL flagging the advisory on 2026-05-15 ([AMD Product Security, 2026-05-12](https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7052.html) · [NCSC-NL NCSC-2026-0158, 2026-05-15](https://advisories.ncsc.nl/advisory?id=NCSC-2026-0158)). The flaw allows a local attacker with code execution on the target system to corrupt the CPU operation (µop) cache and thereby cause instructions to execute at a higher privilege level than intended, enabling local privilege escalation and, in virtualisation contexts, potential degradation of hypervisor-level isolation. Mitigation is delivered as microcode integrated into the **May 2026 Microsoft Windows cumulative update** (the same window as the previously-covered CVE-2026-41089 / 41096 Patch Tuesday set); Fedora has issued separate kernel + microcode updates (advisory IDs per NCSC-NL CSAF references) and Xen has published [XSA-490](https://xenbits.xen.org/xsa/advisory-490.html) for bare-metal hypervisor operators. Lenovo has published a product-security advisory covering affected ThinkPad / ThinkStation / Workstation models for BIOS / UEFI guidance. Attack class: [T1068](https://attack.mitre.org/techniques/T1068/) Exploitation for Privilege Escalation, with elevated relevance in confidential-compute and multi-tenant virtualisation contexts (VDI estates, cloud-hosted VMs on Zen 2 hosts, shared university compute clusters). No in-the-wild exploitation confirmed. Detection / verification: confirm the May 2026 Windows CU includes the AMD microcode revision via the relevant KB and `wmic cpu get name, dataWidth, processorId`; for Linux hypervisors apply distro kernel + microcode updates and reboot; for Xen apply XSA-490; for Lenovo hardware check BIOS / UEFI update guidance per LEN-216977. The local-only attack vector limits external risk; the priority is multi-tenant and virtualisation contexts where guest-to-hypervisor or container-to-host isolation is part of the security boundary. #### CVE Summary Table | CVE | Product | CVSS | EPSS | KEV | Exploited | Patch | Source | |---|---|---|---|---|---|---|---| | CVE-2026-42897 | Microsoft Exchange Server 2016 / 2019 / SE — OWA | 8.1 (v3.1) | n/a | Yes (added 2026-05-15) | Yes — Microsoft confirmed | No permanent patch; EEMS Mitigation M2 (auto / EOMT manual) | [Microsoft MSRC](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-42897) | | CVE-2026-44112 | OpenClaw / Clawdbot — OpenShell sandbox (TOCTOU write escape) | 9.6 (Critical) | n/a | No | No | OpenClaw 2026-04-23 release (GHSA-5h3g-6xhh-rg6p) | [Cyera Research](https://www.cyera.com/blog/claw-chain-cyera-research-unveil-four-chainable-vulnerabilities-in-openclaw) | | CVE-2026-44115 | OpenClaw / Clawdbot — command-parser allowlist bypass | 8.8 (High) | n/a | No | No | OpenClaw 2026-04-23 release (GHSA-wppj-c6mr-83jj) | [Cyera Research](https://www.cyera.com/blog/claw-chain-cyera-research-unveil-four-chainable-vulnerabilities-in-openclaw) | | CVE-2026-44118 | OpenClaw / Clawdbot — MCP loopback `senderIsOwner` trust | 7.8 (High) | n/a | No | No | OpenClaw 2026-04-23 release (GHSA-r6xh-pqhr-v4xh) | [Cyera Research](https://www.cyera.com/blog/claw-chain-cyera-research-unveil-four-chainable-vulnerabilities-in-openclaw) | | CVE-2026-44113 | OpenClaw / Clawdbot — TOCTOU read escape (file disclosure) | 7.7 (High) | n/a | No | No | OpenClaw 2026-04-23 release (GHSA-x3h8-jrgh-p8jx) | [Cyera Research](https://www.cyera.com/blog/claw-chain-cyera-research-unveil-four-chainable-vulnerabilities-in-openclaw) | | CVE-2025-54518 (AMD-SB-7052) | AMD Zen 2 CPUs — µop cache / SoC isolation LPE | 7.3 (CVSS 4.0) | n/a | No | No | May 2026 Windows CU; Fedora kernel + microcode updates; Xen XSA-490 | [AMD Product Security](https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7052.html) |