Search/CVE-2025-21888
● CVE — Medium

CVE-2025-21888

VendorlinuxProductlinux kernelDiscoveredMar 27, 2025UpdatedOct 30, 2026

In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix a WARN during dereg_mr for DM type Memory regions (MR) of type DM (device memory) do not have an associated umem. In the __mlx5_ib_dereg_mr() -> mlx5_free_priv_descs() flow, the code incorrectly takes the wrong branch, attempting to call dma_unmap_single() on a DMA address that is not mapped. This results in a WARN [1], as shown below. The issue is resolved by properly accounting for the DM type and ensuring the correct branch is selected in mlx5_free_priv_descs(). [1] WARNING: CPU: 12 PID: 1346 at drivers/iommu/dma-iommu.c:1230 iommu_dma_unmap_page+0x79/0x90 Modules linked in: ip6table_mangle ip6table_nat ip6table_filter ip6_tables iptable_mangle xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink…

CVSS v3.1
5.5 MEDIUM
EPSS
0.23%
probability of exploitation in 30 days
CISA KEV
Not listed
no confirmed exploitation reported
News coverage
21
sources referencing this CVE
Related IOCs
0
seen in the same coverage
EPSS Trend
Aug 16, 2026 → Oct 31, 2026
▲ 0.05pp
0.18% → 0.23% over 6 tracked changes
CVSS v3.1 Detail
Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
ConfidentialityNONE
IntegrityNONE
AvailabilityHIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Connections
22 relationships
Timeline
disclosure → media coverage
Mar 27, 2025
Disclosure — published as a CVE record. · last revised by NVD Oct 30, 2026
Sep 24, 2025
ubuntu.com reports: USN-7764-1: Linux kernel vulnerabilities
Sep 24, 2025
ubuntu.com reports: USN-7766-1: Linux kernel vulnerabilities
Sep 24, 2025
ubuntu.com reports: USN-7767-1: Linux kernel (Real-time) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7774-1: Linux kernel vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7774-2: Linux kernel (FIPS) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7774-3: Linux kernel (Real-time) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7775-1: Linux kernel (Azure FIPS) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7776-1: Linux kernel (Oracle) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7779-1: Linux kernel (IBM) vulnerabilities
Sep 25, 2025
ubuntu.com reports: USN-7767-2: Linux kernel (Real-time) vulnerabilities
Sep 26, 2025
ubuntu.com reports: USN-7764-2: Linux kernel (HWE) vulnerabilities
Sep 26, 2025
ubuntu.com reports: USN-7775-2: Linux kernel (Azure) vulnerabilities
Oct 1, 2025
ubuntu.com reports: USN-7775-3: Linux kernel (Azure) vulnerabilities
Oct 1, 2025
ubuntu.com reports: USN-7790-1: Linux kernel (Raspberry Pi) vulnerabilities
Oct 1, 2025
ubuntu.com reports: USN-7774-4: Linux kernel (KVM) vulnerabilities
Oct 2, 2025
ubuntu.com reports: USN-7800-1: Linux kernel (Raspberry Pi Real-time) vulnerabilities
Oct 2, 2025
ubuntu.com reports: USN-7801-1: Linux kernel (HWE) vulnerabilities
Oct 2, 2025
ubuntu.com reports: USN-7802-1: Linux kernel (Azure) vulnerabilities
Oct 6, 2025
ubuntu.com reports: USN-7774-5: Linux kernel (NVIDIA Tegra IGX) vulnerabilities
Oct 6, 2025
ubuntu.com reports: USN-7801-2: Linux kernel (Oracle) vulnerabilities
Oct 15, 2025
ubuntu.com reports: USN-7801-3: Linux kernel (Oracle) vulnerabilities