vxlan: keep the last remote linked during FDB flush
In the Linux kernel, the following vulnerability has been resolved: vxlan: keep the last remote linked during FDB flush A non-nexthop FDB entry is expected to have at least one remote while it remains reachable through the FDB hash table. A filtered bulk flush violates this invariant when every remote matches: It unlinks the last remote in vxlan_fdb_dst_destroy() and only afterwards tells vxlan_flush() to destroy the parent FDB entry. An RCU reader can find the parent during this interval. first_remote_rcu() then applies list_entry_rcu() to the empty list head, producing an invalid remote pointer that the receive learning path can read from and write to. When a matching remote is the sole remaining remote, leave it linked and ask the caller to destroy the entire FDB entry. vxlan_fdb_destroy() keeps the remote attached while sending the deletion notification and removing the parent from the lookup structures.
CVE-2026-80838
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-80838
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f",
"lessThan": "2a7c2f00843225d5f037676bca649321f3d024c7",
"versionType": "git"
},
{
"status": "affected",
"version": "c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f",
"lessThan": "a8820c8a7718327e96849782033e7c85a0f6bcfe",
"versionType": "git"
},
{
"status": "affected",
"version": "c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f",
"lessThan": "8ba68fd6cdd1e3c92b92f25c7e48bf7bd51a183c",
"versionType": "git"
},
{
"status": "affected",
"version": "c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f",
"lessThan": "4bbc76ee1b21d3bd045d6d819b2bacd30a6372ab",
"versionType": "git"
},
{
"status": "affected",
"version": "c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f",
"lessThan": "d5d4a7b538b52db63927773a8905fcd9f78a42e2",
"versionType": "git"
}
],
"programFiles": [
"drivers/net/vxlan/vxlan_core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.7"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.7",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.108",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.49",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.13",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2.3",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/vxlan/vxlan_core.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-80838
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #34854 · Revision 1
- Added to Heist Feed
- Publisher date