CVE-2026-80846
xfrm: drop ESP-in-TCP packets with no ingress device
Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: drop ESP-in-TCP packets with no ingress device ESP-in-TCP receives records through the TCP strparser. handle_esp() restores skb->dev from the saved skb_iif before passing the packet into the XFRM input path. Queued TCP data can be processed after the original ingress device has been removed, for example during veth or net namespace teardown. In that case dev_get_by_index_rcu() returns NULL. The XFRM IPv4 and IPv6 input paths both expect skb->dev to be valid while building the route lookup, so queued ESP-in-TCP data can dereference a NULL device. Drop the packet if the saved ingress device can no longer be resolved. Such a packet can no longer be routed through the normal XFRM receive path, and this preserves the existing behaviour for packets whose ingress device still exists.
INFO
Published Date :
Sept. 4, 2026, 4:18 p.m.
Last Modified :
Sept. 4, 2026, 4:18 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the latest version.
- Apply the specific patch for the ESP-in-TCP vulnerability.
- Ensure ingress devices are properly managed during network teardown.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-80846.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-80846 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-2026-80846
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).
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The following list is the news that have been mention
CVE-2026-80846 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-80846 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 04, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: xfrm: drop ESP-in-TCP packets with no ingress device ESP-in-TCP receives records through the TCP strparser. handle_esp() restores skb->dev from the saved skb_iif before passing the packet into the XFRM input path. Queued TCP data can be processed after the original ingress device has been removed, for example during veth or net namespace teardown. In that case dev_get_by_index_rcu() returns NULL. The XFRM IPv4 and IPv6 input paths both expect skb->dev to be valid while building the route lookup, so queued ESP-in-TCP data can dereference a NULL device. Drop the packet if the saved ingress device can no longer be resolved. Such a packet can no longer be routed through the normal XFRM receive path, and this preserves the existing behaviour for packets whose ingress device still exists. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80846.json">CVE-2026-80846</a> Added Reference https://git.kernel.org/stable/c/239d0f71af09dc2029fd4d730cb24b8c83aaa43a Added Reference https://git.kernel.org/stable/c/2dd1609cadff46c4b20ce53b91ab9cce1380456a Added Reference https://git.kernel.org/stable/c/328e40aa774b446969c69b654c52a051a95af8a1 Added Reference https://git.kernel.org/stable/c/6af5cdb03819a5ce6e945992635c6c5e91045367 Added Reference https://git.kernel.org/stable/c/7911e0236616487b89db6bd3ba3f408abd10eb23 Added Reference https://git.kernel.org/stable/c/943d95233b8b4a88994e244fcf466f8c403d63f1 Added Reference https://git.kernel.org/stable/c/c296d25efbc840be24de83f56d43bc47e714ace9 Added Reference https://git.kernel.org/stable/c/e1d7c5ac1c246ce5775f604515de0a59fbf2116e Added Reference https://git.kernel.org/stable/c/f00235f9d12301183d61f75fbe4105506f3e5140