CVE-2025-21800 | net/mlx5: HWS, fix definer's HWS_SET32 macro for negative offset

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: HWS, fix definer's HWS_SET32 macro for negative offset When bit offset for HWS_SET32 macro is negative, UBSAN complains about the shift-out-of-bounds: UBSAN: shift-out-of-bounds in drivers/net/ethernet/mellanox/mlx5/core/steering/hws/definer.c:177:2 shift exponent -8 is negative

Published: 2025-02-27 Last update: 2025-10-29 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-21800 is rated Moderate Risk (41.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.11%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-21800

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-07 0.04% 0.11% +0.07%
2 2025-02-28 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-21800

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]

Weakness enumeration for CVE-2025-21800

OS Trackers for CVE-2025-21800

vendor priority summary link
debian unimportant CVE-2025-21800 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-21800
redhat — — https://access.redhat.com/security/cve/CVE-2025-21800
suse medium CVE-2025-21800 severity moderate: SUSE including 76 source package names (15.7.20.5.1:kernel-default-6.4.0-150700.53.3.1, cluster-md-kmp-default, …), 398 product×package rows across 96 product lines (Container suse/hpc/warewulf4-x86_64/sle-hpc-node, Image SLES15-SP7-Azure-3P, … (96 product lines)): Known Not Affected 247, Fixed 151. https://www.suse.com/security/cve/CVE-2025-21800/
ubuntu medium CVE-2025-21800 medium priority: Ubuntu including 128 source packages (linux, linux-allwinner-5.19, …), 1024 status rows across 8 suites (bionic, focal, jammy, noble, oracular, trusty, upstream, xenial): DNE 702, ignored 146, not-affected 114, released 62. https://ubuntu.com/security/CVE-2025-21800

Affected software / configurations for CVE-2025-21800

Vendor Product Version Raw CPE
linux linux_kernel >= 6.12, < 6.12.13 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.13.2 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2025-21800

cvelogic Threat Intelligence