CVE-2025-21981

CVE-2025-21981 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: ice: fix memory leak in aRFS after reset Fix aRFS (accelerated Receive Flow Steering) structures memory leak by adding a checker to verify if aRFS memory is already allocated while configuring VSI. aRFS objects are allocated in two cases: - as part of VSI initialization (at probe), and - as part of reset handling However, VSI reconfiguration executed during reset involves memory allocation one more time, without prior releasing already allocated resources. This led to the memory leak with the following signature: [root@os-delivery ~]# cat /sys/kernel/debug/kmemleak unreferenced object 0xff3c1ca7252e6000 (size 8192): comm "kworker/0:0", pid 8, jiffies 4296833052 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<ffffffff991ec485>] __kmalloc_cache_noprof+0x275/0x340 [<ffffffffc0a6e06a>] ice_init_arfs+0x3a/0xe0 [ice] [<ffffffffc09f1027>] ice_vsi_cfg_def+0x607/0x850 [ice] [<ffffffffc09f244b>] ice_vsi_setup+0x5b/0x130 [ice] [<ffffffffc09c2131>] ice_init+0x1c1/0x460 [ice] [<ffffffffc09c64af>] ice_probe+0x2af/0x520 [ice] [<ffffffff994fbcd3>] local_pci_probe+0x43/0xa0 [<ffffffff98f07103>] work_for_cpu_fn+0x13/0x20 [<ffffffff98f0b6d9>] process_one_work+0x179/0x390 [<ffffffff98f0c1e9>] worker_thread+0x239/0x340 [<ffffffff98f14abc>] kthread+0xcc/0x100 [<ffffffff98e45a6d>] ret_from_fork+0x2d/0x50 [<ffffffff98e083ba>] ret_from_fork_asm+0x1a/0x30 ...

Frequently asked questions

What is CVE-2025-21981?
In the Linux kernel, the following vulnerability has been resolved: ice: fix memory leak in aRFS after reset Fix aRFS (accelerated Receive Flow Steering) structures memory leak by adding a checker to verify if aRFS memory is already allocated while configuring VSI. aRFS objects are allocated in two cases: - as part of VSI initialization (at probe), and - as part of reset handling However, VSI reconfiguration executed during reset involves memory allocation one more time, without prior releasing already allocated resources. This led to the memory leak with the following signature: [root@os-delivery ~]# cat /sys/kernel/debug/kmemleak unreferenced object 0xff3c1ca7252e6000 (size 8192): comm "kworker/0:0", pid 8, jiffies 4296833052 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<ffffffff991ec485>] __kmalloc_cache_noprof+0x275/0x340 [<ffffffffc0a6e06a>] ice_init_arfs+0x3a/0xe0 [ice] [<ffffffffc09f1027>] ice_vsi_cfg_def+0x607/0x850 [ice] [<ffffffffc09f244b>] ice_vsi_setup+0x5b/0x130 [ice] [<ffffffffc09c2131>] ice_init+0x1c1/0x460 [ice] [<ffffffffc09c64af>] ice_probe+0x2af/0x520 [ice] [<ffffffff994fbcd3>] local_pci_probe+0x43/0xa0 [<ffffffff98f07103>] work_for_cpu_fn+0x13/0x20 [<ffffffff98f0b6d9>] process_one_work+0x179/0x390 [<ffffffff98f0c1e9>] worker_thread+0x239/0x340 [<ffffffff98f14abc>] kthread+0xcc/0x100 [<ffffffff98e45a6d>] ret_from_fork+0x2d/0x50 [<ffffffff98e083ba>] ret_from_fork_asm+0x1a/0x30 ...
How severe is CVE-2025-21981?
CVE-2025-21981 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21981 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21981?
CVE-2025-21981 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21981?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21981 have an EU (EUVD) identifier?
Yes. CVE-2025-21981 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-9339.
When was CVE-2025-21981 published?
CVE-2025-21981 was published on 2025-04-01 and last updated on 2026-06-17.

References

Affected products (7)

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