CVE-2026-45841 (GCVE-0-2026-45841)

Vulnerability from cvelistv5 – Published: 2026-05-27 09:24 – Updated: 2026-05-27 09:24
VLAI
Title
netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO nf_osf_match_one() computes ctx->window % f->wss.val in the OSF_WSS_MODULO branch with no guard for f->wss.val == 0. A CAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a subsequent matching TCP SYN divides by zero and panics the kernel. Reject the bogus fingerprint in nfnl_osf_add_callback() above the per-option for-loop. f->wss is per-fingerprint, not per-option, so the check must run regardless of f->opt_num (including 0). Also reject wss.wc >= OSF_WSS_MAX; nf_osf_match_one() already treats that as "should not happen". Crash: Oops: divide error: 0000 [#1] SMP KASAN NOPTI RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: <IRQ> nf_osf_match (net/netfilter/nfnetlink_osf.c:220) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:348) nf_hook_slow (net/netfilter/core.c:622) ip_local_deliver (net/ipv4/ip_input.c:265) ip_rcv (include/linux/skbuff.h:1162) __netif_receive_skb_one_core (net/core/dev.c:6181) process_backlog (net/core/dev.c:6642) __napi_poll (net/core/dev.c:7710) net_rx_action (net/core/dev.c:7945) handle_softirqs (kernel/softirq.c:622)
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 , < 8def8fbd23f40e945febe913d04b731012ce0082 (git)
Affected: 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 , < c55940895245d8ef658ab381248a28755218d625 (git)
Affected: 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 , < fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f (git)
Affected: 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 , < 9a05e195618a6d474f2bcd5b6376d0ffc2f00366 (git)
Affected: 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 , < 2195574dc6d9017d32ac346987e12659f931d932 (git)
Create a notification for this product.
Linux Linux Affected: 2.6.31
Unaffected: 0 , < 2.6.31 (semver)
Unaffected: 6.6.141 , ≤ 6.6.* (semver)
Unaffected: 6.12.91 , ≤ 6.12.* (semver)
Unaffected: 6.18.33 , ≤ 6.18.* (semver)
Unaffected: 7.0.10 , ≤ 7.0.* (semver)
Unaffected: 7.1-rc1 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/netfilter/nfnetlink_osf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8def8fbd23f40e945febe913d04b731012ce0082",
              "status": "affected",
              "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384",
              "versionType": "git"
            },
            {
              "lessThan": "c55940895245d8ef658ab381248a28755218d625",
              "status": "affected",
              "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384",
              "versionType": "git"
            },
            {
              "lessThan": "fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f",
              "status": "affected",
              "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384",
              "versionType": "git"
            },
            {
              "lessThan": "9a05e195618a6d474f2bcd5b6376d0ffc2f00366",
              "status": "affected",
              "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384",
              "versionType": "git"
            },
            {
              "lessThan": "2195574dc6d9017d32ac346987e12659f931d932",
              "status": "affected",
              "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/netfilter/nfnetlink_osf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.31"
            },
            {
              "lessThan": "2.6.31",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.141",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.91",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.33",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.141",
                  "versionStartIncluding": "2.6.31",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.91",
                  "versionStartIncluding": "2.6.31",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.33",
                  "versionStartIncluding": "2.6.31",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.10",
                  "versionStartIncluding": "2.6.31",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1-rc1",
                  "versionStartIncluding": "2.6.31",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO\n\nnf_osf_match_one() computes ctx-\u003ewindow % f-\u003ewss.val in the\nOSF_WSS_MODULO branch with no guard for f-\u003ewss.val == 0. A\nCAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a\nsubsequent matching TCP SYN divides by zero and panics the kernel.\n\nReject the bogus fingerprint in nfnl_osf_add_callback() above the\nper-option for-loop. f-\u003ewss is per-fingerprint, not per-option, so\nthe check must run regardless of f-\u003eopt_num (including 0). Also\nreject wss.wc \u003e= OSF_WSS_MAX; nf_osf_match_one() already treats that\nas \"should not happen\".\n\nCrash:\n Oops: divide error: 0000 [#1] SMP KASAN NOPTI\n RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98)\n Call Trace:\n \u003cIRQ\u003e\n  nf_osf_match (net/netfilter/nfnetlink_osf.c:220)\n  xt_osf_match_packet (net/netfilter/xt_osf.c:32)\n  ipt_do_table (net/ipv4/netfilter/ip_tables.c:348)\n  nf_hook_slow (net/netfilter/core.c:622)\n  ip_local_deliver (net/ipv4/ip_input.c:265)\n  ip_rcv (include/linux/skbuff.h:1162)\n  __netif_receive_skb_one_core (net/core/dev.c:6181)\n  process_backlog (net/core/dev.c:6642)\n  __napi_poll (net/core/dev.c:7710)\n  net_rx_action (net/core/dev.c:7945)\n  handle_softirqs (kernel/softirq.c:622)"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-27T09:24:40.805Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/8def8fbd23f40e945febe913d04b731012ce0082"
        },
        {
          "url": "https://git.kernel.org/stable/c/c55940895245d8ef658ab381248a28755218d625"
        },
        {
          "url": "https://git.kernel.org/stable/c/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f"
        },
        {
          "url": "https://git.kernel.org/stable/c/9a05e195618a6d474f2bcd5b6376d0ffc2f00366"
        },
        {
          "url": "https://git.kernel.org/stable/c/2195574dc6d9017d32ac346987e12659f931d932"
        }
      ],
      "title": "netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-45841",
    "datePublished": "2026-05-27T09:24:40.805Z",
    "dateReserved": "2026-05-13T15:03:33.078Z",
    "dateUpdated": "2026-05-27T09:24:40.805Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-45841",
      "date": "2026-05-28",
      "epss": "0.00018",
      "percentile": "0.05152"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-45841\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-05-27T11:16:23.493\",\"lastModified\":\"2026-05-27T14:48:03.013\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnetfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO\\n\\nnf_osf_match_one() computes ctx-\u003ewindow % f-\u003ewss.val in the\\nOSF_WSS_MODULO branch with no guard for f-\u003ewss.val == 0. A\\nCAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a\\nsubsequent matching TCP SYN divides by zero and panics the kernel.\\n\\nReject the bogus fingerprint in nfnl_osf_add_callback() above the\\nper-option for-loop. f-\u003ewss is per-fingerprint, not per-option, so\\nthe check must run regardless of f-\u003eopt_num (including 0). Also\\nreject wss.wc \u003e= OSF_WSS_MAX; nf_osf_match_one() already treats that\\nas \\\"should not happen\\\".\\n\\nCrash:\\n Oops: divide error: 0000 [#1] SMP KASAN NOPTI\\n RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98)\\n Call Trace:\\n \u003cIRQ\u003e\\n  nf_osf_match (net/netfilter/nfnetlink_osf.c:220)\\n  xt_osf_match_packet (net/netfilter/xt_osf.c:32)\\n  ipt_do_table (net/ipv4/netfilter/ip_tables.c:348)\\n  nf_hook_slow (net/netfilter/core.c:622)\\n  ip_local_deliver (net/ipv4/ip_input.c:265)\\n  ip_rcv (include/linux/skbuff.h:1162)\\n  __netif_receive_skb_one_core (net/core/dev.c:6181)\\n  process_backlog (net/core/dev.c:6642)\\n  __napi_poll (net/core/dev.c:7710)\\n  net_rx_action (net/core/dev.c:7945)\\n  handle_softirqs (kernel/softirq.c:622)\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/2195574dc6d9017d32ac346987e12659f931d932\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8def8fbd23f40e945febe913d04b731012ce0082\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/9a05e195618a6d474f2bcd5b6376d0ffc2f00366\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c55940895245d8ef658ab381248a28755218d625\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.