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FKIE_CVE-2026-80901

Vulnerability from fkie_nvd - Published: 2026-09-04 18:17 - Updated: 2026-09-04 18:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: ipvs: fix the checksum validations ip_vs_in_icmp_v6() is missing checksum validation for ICMPv6 packets from clients. In fact, as for TCP/UDP we should validate the checksum for ICMP packets only when we mangle the packets on MASQ or on reply for tunnel. Also, Sashiko points out that handle_response_icmp() being common for IPv4 and IPv6 is missing the pseudo-header calculation while validating ICMPv6 messages from real servers which is a problem if checksum is not validated by the hardware. Fix the problems by creating ip_vs_checksum_common_check() helper and use it for TCP/UDP/ICMP both for IPv4 and IPv6. Rely on the nf_checksum() for validating the ICMP messages but use it also for TCP and UDP. Use correct IP offset for IP_VS_DBG_RL_PKT for TCP/UDP/SCTP. IPVS packets (TCP/UDP/SCTP/ICMP) do not need checksum validation on LOCAL_OUT (local clients or local real servers) and on FORWARD (traffic from servers on LAN). Do it only on LOCAL_IN, in case nf_checksum() is not called on PRE_ROUTING. Also, ip_vs_checksum_complete() can be marked static.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/00eb23829fd08df1b5e057cb6b625996a70e7e65
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5558a85add073215b298f3e044ff9a6d86d714ae
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9cbe2c0fdb71904ee929b1851cdc1c73341a03c0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b3869d9b54e76dff64118dee4c8fd9302fcd5171
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d418d73acf8be62744dc47359dfdde8c2148845d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e876b75b9020a97bbdc79721e7fc749024891c65
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/ip_vs.h",
            "net/netfilter/ipvs/ip_vs_core.c",
            "net/netfilter/ipvs/ip_vs_proto_sctp.c",
            "net/netfilter/ipvs/ip_vs_proto_tcp.c",
            "net/netfilter/ipvs/ip_vs_proto_udp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d418d73acf8be62744dc47359dfdde8c2148845d",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            },
            {
              "lessThan": "b3869d9b54e76dff64118dee4c8fd9302fcd5171",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            },
            {
              "lessThan": "9cbe2c0fdb71904ee929b1851cdc1c73341a03c0",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            },
            {
              "lessThan": "00eb23829fd08df1b5e057cb6b625996a70e7e65",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            },
            {
              "lessThan": "5558a85add073215b298f3e044ff9a6d86d714ae",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            },
            {
              "lessThan": "e876b75b9020a97bbdc79721e7fc749024891c65",
              "status": "affected",
              "version": "2a3b791e6e1169f374224d164738e9f7be703d77",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/net/ip_vs.h",
            "net/netfilter/ipvs/ip_vs_core.c",
            "net/netfilter/ipvs/ip_vs_proto_sctp.c",
            "net/netfilter/ipvs/ip_vs_proto_tcp.c",
            "net/netfilter/ipvs/ip_vs_proto_udp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.28"
            },
            {
              "lessThan": "2.6.28",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.151",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.103",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.44",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: fix the checksum validations\n\nip_vs_in_icmp_v6() is missing checksum validation for ICMPv6\npackets from clients. In fact, as for TCP/UDP we should\nvalidate the checksum for ICMP packets only when we\nmangle the packets on MASQ or on reply for tunnel.\n\nAlso, Sashiko points out that handle_response_icmp() being\ncommon for IPv4 and IPv6 is missing the pseudo-header\ncalculation while validating ICMPv6 messages from real\nservers which is a problem if checksum is not validated\nby the hardware.\n\nFix the problems by creating ip_vs_checksum_common_check()\nhelper and use it for TCP/UDP/ICMP both for IPv4 and IPv6.\nRely on the nf_checksum() for validating the ICMP messages\nbut use it also for TCP and UDP.\n\nUse correct IP offset for IP_VS_DBG_RL_PKT for TCP/UDP/SCTP.\n\nIPVS packets (TCP/UDP/SCTP/ICMP) do not need checksum\nvalidation on LOCAL_OUT (local clients or local real\nservers) and on FORWARD (traffic from servers on LAN).\nDo it only on LOCAL_IN, in case nf_checksum() is not\ncalled on PRE_ROUTING.\n\nAlso, ip_vs_checksum_complete() can be marked static."
    }
  ],
  "id": "CVE-2026-80901",
  "lastModified": "2026-09-04T18:17:58.767",
  "metrics": {},
  "published": "2026-09-04T18:17:58.767",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/00eb23829fd08df1b5e057cb6b625996a70e7e65"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5558a85add073215b298f3e044ff9a6d86d714ae"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9cbe2c0fdb71904ee929b1851cdc1c73341a03c0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b3869d9b54e76dff64118dee4c8fd9302fcd5171"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d418d73acf8be62744dc47359dfdde8c2148845d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e876b75b9020a97bbdc79721e7fc749024891c65"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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