7.8
HIGH
CVE-2025-21855
IBM IBMVNIC Use-After-Free Vulnerability
Description

In the Linux kernel, the following vulnerability has been resolved: ibmvnic: Don't reference skb after sending to VIOS Previously, after successfully flushing the xmit buffer to VIOS, the tx_bytes stat was incremented by the length of the skb. It is invalid to access the skb memory after sending the buffer to the VIOS because, at any point after sending, the VIOS can trigger an interrupt to free this memory. A race between reading skb->len and freeing the skb is possible (especially during LPM) and will result in use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in ibmvnic_xmit+0x75c/0x1808 [ibmvnic] Read of size 4 at addr c00000024eb48a70 by task hxecom/14495 <...> Call Trace: [c000000118f66cf0] [c0000000018cba6c] dump_stack_lvl+0x84/0xe8 (unreliable) [c000000118f66d20] [c0000000006f0080] print_report+0x1a8/0x7f0 [c000000118f66df0] [c0000000006f08f0] kasan_report+0x128/0x1f8 [c000000118f66f00] [c0000000006f2868] __asan_load4+0xac/0xe0 [c000000118f66f20] [c0080000046eac84] ibmvnic_xmit+0x75c/0x1808 [ibmvnic] [c000000118f67340] [c0000000014be168] dev_hard_start_xmit+0x150/0x358 <...> Freed by task 0: kasan_save_stack+0x34/0x68 kasan_save_track+0x2c/0x50 kasan_save_free_info+0x64/0x108 __kasan_mempool_poison_object+0x148/0x2d4 napi_skb_cache_put+0x5c/0x194 net_tx_action+0x154/0x5b8 handle_softirqs+0x20c/0x60c do_softirq_own_stack+0x6c/0x88 <...> The buggy address belongs to the object at c00000024eb48a00 which belongs to the cache skbuff_head_cache of size 224 ==================================================================

INFO

Published Date :

March 12, 2025, 10:15 a.m.

Last Modified :

March 28, 2025, 4:15 p.m.

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Remotely Exploitable :

No

Impact Score :

5.9

Exploitability Score :

1.8
Affected Products

The following products are affected by CVE-2025-21855 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-21855 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-21855 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Mar. 28, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
  • Initial Analysis by [email protected]

    Mar. 13, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 from (excluding) 6.13.5 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 from (excluding) 6.6.80 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 from (excluding) 6.12.17 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.5 from (excluding) 6.1.130
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/093b0e5c90592773863f300b908b741622eef597 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/25dddd01dcc8ef3acff964dbb32eeb0d89f098e9 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/501ac6a7e21b82e05207c6b4449812d82820f306 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/abaff2717470e4b5b7c0c3a90e128b211a23da09 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/bdf5d13aa05ec314d4385b31ac974d6c7e0997c9 Types: Patch
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Mar. 12, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: ibmvnic: Don't reference skb after sending to VIOS Previously, after successfully flushing the xmit buffer to VIOS, the tx_bytes stat was incremented by the length of the skb. It is invalid to access the skb memory after sending the buffer to the VIOS because, at any point after sending, the VIOS can trigger an interrupt to free this memory. A race between reading skb->len and freeing the skb is possible (especially during LPM) and will result in use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in ibmvnic_xmit+0x75c/0x1808 [ibmvnic] Read of size 4 at addr c00000024eb48a70 by task hxecom/14495 <...> Call Trace: [c000000118f66cf0] [c0000000018cba6c] dump_stack_lvl+0x84/0xe8 (unreliable) [c000000118f66d20] [c0000000006f0080] print_report+0x1a8/0x7f0 [c000000118f66df0] [c0000000006f08f0] kasan_report+0x128/0x1f8 [c000000118f66f00] [c0000000006f2868] __asan_load4+0xac/0xe0 [c000000118f66f20] [c0080000046eac84] ibmvnic_xmit+0x75c/0x1808 [ibmvnic] [c000000118f67340] [c0000000014be168] dev_hard_start_xmit+0x150/0x358 <...> Freed by task 0: kasan_save_stack+0x34/0x68 kasan_save_track+0x2c/0x50 kasan_save_free_info+0x64/0x108 __kasan_mempool_poison_object+0x148/0x2d4 napi_skb_cache_put+0x5c/0x194 net_tx_action+0x154/0x5b8 handle_softirqs+0x20c/0x60c do_softirq_own_stack+0x6c/0x88 <...> The buggy address belongs to the object at c00000024eb48a00 which belongs to the cache skbuff_head_cache of size 224 ==================================================================
    Added Reference https://git.kernel.org/stable/c/093b0e5c90592773863f300b908b741622eef597
    Added Reference https://git.kernel.org/stable/c/25dddd01dcc8ef3acff964dbb32eeb0d89f098e9
    Added Reference https://git.kernel.org/stable/c/501ac6a7e21b82e05207c6b4449812d82820f306
    Added Reference https://git.kernel.org/stable/c/abaff2717470e4b5b7c0c3a90e128b211a23da09
    Added Reference https://git.kernel.org/stable/c/bdf5d13aa05ec314d4385b31ac974d6c7e0997c9
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-21855 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-21855 weaknesses.

CVSS31 - Vulnerability Scoring System
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