What is the CVSS score of EUVD-2026-48967?

EUVD-2026-48967 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.2%.

Which versions of Linux Kernel are affected by EUVD-2026-48967?

A memory vulnerability in Linux kernel multicast handling could allow local users to cause system crashes or unexpected behavior.. A patch is available.

How to fix or mitigate EUVD-2026-48967?

Within 24 hours, identify all Linux systems and reference Ubuntu USN-8726/8727-1 to assess which kernel versions are vulnerable. Within 7 days, apply vendor-released patches from your Linux distribution (Ubuntu, RHEL, Debian, etc.) to test and non-production systems, validating network functionality afterward. Within 30 days, deploy patches to all production Linux systems, prioritizing multi-tenant platforms and cloud environments; schedule maintenance windows with operations to minimize service disruption.

Linux Kernel EUVD-2026-48967

| CVE-2026-64423 HIGH

Use After Free (CWE-416)

2026-07-25 Linux

GHSA-wx6r-3m2q-4mm6

Linux Use After Free Memory Corruption

7.8

CVSS 3.1 · Vendor: Linux

Severity by source

Vendor (Linux) PRIMARY

7.8 HIGH

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

vuln.today AI

7.0 HIGH

Race condition between device teardown and softirq packet processing requires specific timing, elevating AC to H; low-privilege multicast join is sufficient to set up the precondition.

3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

4.0 AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

SUSE

HIGH

qualitative

Red Hat

5.5 MEDIUM

qualitative

Primary rating from Vendor (Linux).

CVSS VectorVendor: Linux

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Metadata Corrected

Sep 16, 2026 - 09:40 vuln.today

tag: Information Disclosure removed

Analysis Generated

Jul 27, 2026 - 05:51 vuln.today

CVSS changed

Jul 27, 2026 - 05:22 NVD

7.8 (HIGH)

Patch available

Jul 25, 2026 - 11:18 EUVD

CVE Published

Jul 25, 2026 - 08:51 cve.org

HIGH 7.8

CVE Published

Jul 25, 2026 - 08:51 cve.org

UNKNOWN (no severity yet)

DescriptionCVE.org

In the Linux kernel, the following vulnerability has been resolved:

ipv4: igmp: remove multicast group from hash table on device destruction

When a device is destroyed under RTNL, ip_mc_destroy_dev() iterates through the multicast list and calls ip_ma_put() on each membership, scheduling them for RCU reclamation. However, they are not unlinked from the device's multicast hash table (mc_hash).

Since the device remains published in dev->ip_ptr until after ip_mc_destroy_dev() completes, concurrent RCU readers traversing mc_hash can still locate and access the multicast group after its refcount is decremented. If the RCU callback runs and frees the group while a reader is accessing it, a use-after-free occurs.

Fix this by unlinking the multicast group from mc_hash using ip_mc_hash_remove() before scheduling it for reclamation.

BUG: KASAN: slab-use-after-free in ip_check_mc_rcu+0x149/0x3f0 Read of size 4 at addr ffff888009bf1408 by task mausezahn/2276

Call Trace: <IRQ> dump_stack_lvl+0x67/0x90 print_report+0x175/0x7c0 kasan_report+0x147/0x180 ip_check_mc_rcu+0x149/0x3f0 udp_v4_early_demux+0x36d/0x12d0 ip_rcv_finish_core+0xb8b/0x1390 ip_rcv_finish+0x54/0x120 NF_HOOK+0x213/0x2b0 __netif_receive_skb+0x126/0x340 process_backlog+0x4f2/0xf00 __napi_poll+0x92/0x2c0 net_rx_action+0x583/0xc60 handle_softirqs+0x236/0x7f0 do_softirq+0x57/0x80 </IRQ>

Allocated by task 2239: kasan_save_track+0x3e/0x80 __kasan_kmalloc+0x72/0x90 ____ip_mc_inc_group+0x31a/0xa40 __ip_mc_join_group+0x334/0x3f0 do_ip_setsockopt+0x16fa/0x2010 ip_setsockopt+0x3f/0x90 do_sock_setsockopt+0x1ad/0x300

Freed by task 0: kasan_save_track+0x3e/0x80 kasan_save_free_info+0x40/0x50 __kasan_slab_free+0x3a/0x60 __rcu_free_sheaf_prepare+0xd4/0x220 rcu_free_sheaf+0x36/0x190 rcu_core+0x8d9/0x12f0 handle_softirqs+0x236/0x7f0

AnalysisAI

Use-after-free in the Linux kernel IPv4 IGMP subsystem allows a local low-privileged attacker to trigger kernel memory corruption or a system crash by racing network device destruction against concurrent multicast group lookups in softirq context. During ip_mc_destroy_dev(), multicast membership entries are scheduled for RCU reclamation via ip_ma_put() but are not unlinked from the per-device mc_hash table; concurrent softirq-path readers such as ip_check_mc_rcu() can then dereference a freed slab object, as confirmed by the embedded KASAN trace showing a read of freed memory during UDP packet processing. No public exploit code or CISA KEV listing exists at time of analysis; Ubuntu USN-8726/8727-1 and a Siemens ICS advisory confirm active patching across distributions.

Technical ContextAI

The vulnerability resides in the IPv4 IGMP (Internet Group Management Protocol) implementation in net/ipv4/igmp.c. When a network device is destroyed under RTNL, ip_mc_destroy_dev() iterates the in_device multicast list and calls ip_ma_put() on each ip_mc_list entry, which decrements the reference count and schedules the structure for RCU callback-based freeing. However, it omits calling ip_mc_hash_remove() to unlink entries from the device's mc_hash table. Because dev->ip_ptr (the in_device containing mc_hash) remains visible to RCU readers until after ip_mc_destroy_dev() completes, softirq-path functions traversing mc_hash - specifically ip_check_mc_rcu() invoked from udp_v4_early_demux during packet receive - can locate and dereference the already-freed ip_mc_list structure. CWE-416 (Use After Free) correctly identifies the root cause. The bug was introduced in kernel 3.11 when mc_hash was added to the IGMP path. CPE: cpe:2.3:a:linux:linux:*:*:*:*:*:*:*:*.

RemediationAI

Upgrade to a patched Linux kernel stable release: 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4, or 7.2-rc3 or later for the respective stable series. Ubuntu users should apply the kernel packages described in USN-8726-1 and USN-8727-1. Siemens product operators should follow SSA-019113 remediation guidance. Where patching is immediately infeasible, restricting untrusted local users from joining multicast groups (e.g., via network namespace isolation in containers, or restricting IP_ADD_MEMBERSHIP setsockopt access through SELinux/AppArmor policy) limits the preconditions for the race; note this does not protect against the race being triggered by privileged teardown paths such as container network cleanup. The trade-off of namespace isolation is increased operational complexity.

Same weakness CWE-416 – Use After Free

View all

CVE-2019-0708 CRITICAL POC

9.8

CVE-2015-5119 CRITICAL POC

9.8

CVE-2014-0322 HIGH POC

8.8

CVE-2012-4792 HIGH POC

8.8

CVE-2009-4324 HIGH POC

7.8

CVE-2015-0313 CRITICAL POC

9.8

CVE-2015-5122 CRITICAL POC

9.8

CVE-2013-2551 HIGH POC

8.8

Same technique Use After Free

View all

CVE-2015-5119 CRITICAL POC

9.8

CVE-2014-0322 HIGH POC

8.8

CVE-2012-4792 HIGH POC

8.8

CVE-2009-4324 HIGH POC

7.8

CVE-2015-0313 CRITICAL POC

9.8

CVE-2015-5122 CRITICAL POC

9.8

CVE-2013-2551 HIGH POC

8.8

CVE-2012-4969 HIGH POC

8.1

Vendor StatusVendor

SUSE

Severity: Important

Product	Status
SUSE Linux Enterprise Desktop 15 SP7	Affected
SUSE Linux Enterprise Desktop 15 SP7	Affected
SUSE Linux Enterprise High Availability Extension 15 SP7	Affected
SUSE Linux Enterprise High Availability Extension 15 SP7	Affected
SUSE Linux Enterprise High Availability Extension 16.0	Affected

EUVD-2026-48967 vulnerability details – vuln.today

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Linux Kernel EUVD-2026-48967

Severity by source

CVSS VectorVendor: Linux

Lifecycle Timeline

DescriptionCVE.org

AnalysisAI

Technical ContextAI

RemediationAI

Same weakness CWE-416 – Use After Free

Same technique Use After Free

Vendor StatusVendor

SUSE

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External POC / Exploit Code