CVE-2026-98794 (GCVE-0-2026-98794)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:48 – Updated: 2026-10-30 12:39
VLAI
Title
ipvs: filter some flags received in the backup server
Summary
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.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7018 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < ef3cd6c0b826e50dc21653b32552e258de6fd51c (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < 3a9f5459db60311643bfbadf019f6d5370f2f26a (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < 438a5335276614186d6a96b8e7bddce811ad4ad6 (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0 (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < f4cd1db7d421e82945713a36084bb0c35b75b27e (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < 55d033324f67a15ff56be6d38d6e87f644e0ed62 (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < 45a93111835ccfea7d969ec73588e33745fd9834 (git)
Affected: 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 , < f96e91748f6304668fe647e686d199d7207d36f1 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.14
Unaffected: 0 , < 2.6.14 (semver)
Unaffected: 5.10.273 , ≤ 5.10.* (semver)
Unaffected: 5.15.224 , ≤ 5.15.* (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.113 , ≤ 6.12.* (semver)
Unaffected: 6.18.56 , ≤ 6.18.* (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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        }
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    "cveId": "CVE-2026-98794",
    "datePublished": "2026-10-18T15:48:37.924Z",
    "dateReserved": "2026-09-25T10:25:14.370Z",
    "dateUpdated": "2026-10-30T12:39:52.699Z",
    "state": "PUBLISHED"
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          }
        ],
        "id": "CVE-2026-98794",
        "lastModified": "2026-10-30T13:21:28.253",
        "metrics": {},
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        "vulnStatus": "Received"
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      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-23T15:23:11+00:00",
      "cve": "CVE-2026-98794",
      "id": "CVE-2026-98794",
      "initial_release_date": "2026-10-18T00:00:00+00:00",
      "product_status:known_affected": "278",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ipvs: filter some flags received in the backup server",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98794.json",
      "version": "3"
    }
  }
}



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