# CVE-2025-38733: linux: In the Linux kernel, the following vulnerability has been resolved: s390/mm: Do not map lowcore with identity mappin... CVE-2025-38733 is fixed in 13 products on 1 platform, first by DEBIAN-CVE-2025-38733, released September 5, 2025. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2025-38733 - Priority: Routine - CVSS: 5.5 (medium) - EPSS: 0.0017 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Sep 5, 2025 ## Description In the Linux kernel, the following vulnerability has been resolved: s390/mm: Do not map lowcore with identity mapping Since the identity mapping is pinned to address zero the lowcore is always also mapped to address zero, this happens regardless of the relocate_lowcore command line option. If the option is specified the lowcore is mapped twice, instead of only once. This means that NULL pointer accesses will succeed instead of causing an exception (low address protection still applies, but covers only parts). To fix this never map the first two pages of physical memory with the identity mapping. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | dtb-aarch64 opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-64kb opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-64kb sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-default opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-default sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-default-base opensuse-leap 16.0 | 6.12.0-160000.6.1.160000.2.4 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-default-base sles 16.0 | 6.12.0-160000.6.1.160000.2.4 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-docs opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-docs sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-kvmsmall opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-kvmsmall sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-obs-build opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-obs-qa opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-obs-qa sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-rt opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-source opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-source sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-syms opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-syms sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | kernel-zfcpdump opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 | | Linux | kernel-zfcpdump sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 | | Linux | linux Debian 13.5 (trixie) | 6.12.48-1 | [DEBIAN-CVE-2025-38733](https://patchblox.com/security/data/fix/linux/debian-cve-2025-38733.md) | Sep 5, 2025 | | Linux | linux Debian 14 | 6.16.5-1 | [DEBIAN-CVE-2025-38733](https://patchblox.com/security/data/fix/linux/debian-cve-2025-38733.md) | Sep 5, 2025 | --- Data as of 2026-11-08T13:06:02Z UTC. 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