5.5
MEDIUM CVSS 3.1
CVE-2026-53220
netfilter: revalidate bridge ports
Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: revalidate bridge ports ebt_redirect_tg() dereferences br_port_get_rcu() return without a NULL check, causing a kernel panic when the bridge port has been removed between the original hook invocation and an NFQUEUE reinject. A mere NULL check isn't sufficient, however. As sashiko review points out userspace can not only remove the port from the bridge, it could also place the device in a different virtual device, e.g. macvlan. If this happens, we must drop the packet, there is no way for us to reinject it into the bridge path. Switch to _upper API, we don't need the bridge port structure. Also, this fix keeps another bug intact: Both nfnetlink_log and nfnetlink_queue use CONFIG_BRIDGE_NETFILTER too aggressive, which prevents certain logging features when queueing in bridge family: NETFILTER_FAMILY_BRIDGE can be enabled while the old CONFIG_BRIDGE_NETFILTER cruft is off. Fixes tag is a common ancestor, this was always broken.

INFO

Published Date :

June 25, 2026, 9:16 a.m.

Last Modified :

July 2, 2026, 8:49 p.m.

Remotely Exploit :

No

Source :

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

The following products are affected by CVE-2026-53220 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
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update the Linux kernel to resolve a bridge port revalidation issue causing kernel panics.
  • Apply the Linux kernel update to the netfilter subsystem.
  • Ensure bridge netfilter configurations are correct.
  • Test for stability after applying the patch.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53220 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-2026-53220 weaknesses.

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-2026-53220 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-53220 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.

  • Initial Analysis by [email protected]

    Jul. 02, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-476
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.36 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.13 *cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 2.6.36 up to (excluding) 6.12.94
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/43330a1e8aace6b5a8de9aba127e9e394ab49b0f Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/4beffcd726e2a731cea4dc18e1fbc55c8d76f1a0 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/ccb9fd4b87538ccf19ccff78ee26700526d94867 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/d4b1301fd3c9e5e105fd3767c68bc4ba558bb228 Types: Patch
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'f350a0a87374418635689471606454abc7beaa3a', 'lessThan': '43330a1e8aace6b5a8de9aba127e9e394ab49b0f', 'versionType': 'git'}, {'status': 'affected', 'version': 'f350a0a87374418635689471606454abc7beaa3a', 'lessThan': '4beffcd726e2a731cea4dc18e1fbc55c8d76f1a0', 'versionType': 'git'}, {'status': 'affected', 'version': 'f350a0a87374418635689471606454abc7beaa3a', 'lessThan': 'd4b1301fd3c9e5e105fd3767c68bc4ba558bb228', 'versionType': 'git'}, {'status': 'affected', 'version': 'f350a0a87374418635689471606454abc7beaa3a', 'lessThan': 'ccb9fd4b87538ccf19ccff78ee26700526d94867', 'versionType': 'git'}], 'programFiles': ['net/bridge/netfilter/ebt_dnat.c', 'net/bridge/netfilter/ebt_redirect.c', 'net/netfilter/nfnetlink_log.c', 'net/netfilter/nfnetlink_queue.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2.6.36'}, {'status': 'unaffected', 'version': '0', 'lessThan': '2.6.36', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.12.94', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.36', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.13', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/bridge/netfilter/ebt_dnat.c', 'net/bridge/netfilter/ebt_redirect.c', 'net/netfilter/nfnetlink_log.c', 'net/netfilter/nfnetlink_queue.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: netfilter: revalidate bridge ports ebt_redirect_tg() dereferences br_port_get_rcu() return without a NULL check, causing a kernel panic when the bridge port has been removed between the original hook invocation and an NFQUEUE reinject. A mere NULL check isn't sufficient, however. As sashiko review points out userspace can not only remove the port from the bridge, it could also place the device in a different virtual device, e.g. macvlan. If this happens, we must drop the packet, there is no way for us to reinject it into the bridge path. Switch to _upper API, we don't need the bridge port structure. Also, this fix keeps another bug intact: Both nfnetlink_log and nfnetlink_queue use CONFIG_BRIDGE_NETFILTER too aggressive, which prevents certain logging features when queueing in bridge family: NETFILTER_FAMILY_BRIDGE can be enabled while the old CONFIG_BRIDGE_NETFILTER cruft is off. Fixes tag is a common ancestor, this was always broken.
    Added Reference https://git.kernel.org/stable/c/43330a1e8aace6b5a8de9aba127e9e394ab49b0f
    Added Reference https://git.kernel.org/stable/c/4beffcd726e2a731cea4dc18e1fbc55c8d76f1a0
    Added Reference https://git.kernel.org/stable/c/ccb9fd4b87538ccf19ccff78ee26700526d94867
    Added Reference https://git.kernel.org/stable/c/d4b1301fd3c9e5e105fd3767c68bc4ba558bb228
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.