ipvs: filter some flags received in the backup server
In the Linux kernel, the following vulnerability has been resolved: ipvs: filter some flags received in the backup server While the IPVS SYNC protocol is not secure by design we can still protect the backup server from messages that can wreak havoc. This commit addresses problems from received connection flags or their combinations. We now drop messages as follows: 1. the NO_CPORT+TEMPLATE combination allows lookups for normal connections to hit template which can break in many ways. While the master does not sync connections with NO_CPORT flag, i.e. before they are established, we still accept NO_CPORT without TEMPLATE. 2. ONE_PACKET: it is not sent by master, so we do not expect it in backup. Before now it was ignored by IP_VS_CONN_F_BACKUP_MASK for protocol v1 while protocol v0 created connections that are not hashed and dropped immediately. Better to apply the IP_VS_CONN_F_BACKUP_MASK also to the flags from v0 messages for consistency with v1.
CVE-2026-98794
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-2026-98794
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": "87375ab47cd0ba04124c6d3fd80db5c368f5dcb6",
"lessThan": "d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0",
"versionType": "git"
},
{
"status": "affected",
"version": "87375ab47cd0ba04124c6d3fd80db5c368f5dcb6",
"lessThan": "f4cd1db7d421e82945713a36084bb0c35b75b27e",
"versionType": "git"
},
{
"status": "affected",
"version": "87375ab47cd0ba04124c6d3fd80db5c368f5dcb6",
"lessThan": "55d033324f67a15ff56be6d38d6e87f644e0ed62",
"versionType": "git"
},
{
"status": "affected",
"version": "87375ab47cd0ba04124c6d3fd80db5c368f5dcb6",
"lessThan": "45a93111835ccfea7d969ec73588e33745fd9834",
"versionType": "git"
},
{
"status": "affected",
"version": "87375ab47cd0ba04124c6d3fd80db5c368f5dcb6",
"lessThan": "f96e91748f6304668fe647e686d199d7207d36f1",
"versionType": "git"
}
],
"programFiles": [
"net/netfilter/ipvs/ip_vs_sync.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.14"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/ipvs/ip_vs_sync.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98794
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #48982 · Revision 1
- Added to Heist Feed
- Publisher date