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EUVD-2026-367596

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 08:36

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T08:36:27.922342+00:00",
  "id": "EUVD-2026-367596"
}

CVE-2026-89487 (GCVE-0-2026-89487)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:43 – Updated: 2026-09-14 12:00

Title

openvswitch: only skb_tx_error() a packet we are about to drop

Summary

In the Linux kernel, the following vulnerability has been resolved: openvswitch: only skb_tx_error() a packet we are about to drop queue_userspace_packet() borrows the packet skb -- it only copies it into a private netlink message (user_skb) and does not own it; on return do_execute_actions() keeps forwarding it through the flow's remaining actions. Its error path nevertheless calls skb_tx_error(skb), which via skb_zcopy_clear() does skb_shinfo(skb)->flags &= ~SKBFL_ALL_ZEROCOPY, stripping SKBFL_SHARED_FRAG from that live skb (skb_tx_error()'s kerneldoc says "skb must be freed afterwards"). For a MSG_ZEROCOPY skb carrying page-cache frags, SKBFL_SHARED_FRAG is what makes esp_input() skb_cow_data() before in-place AEAD; once it is stripped a later local ESP-in-UDP delivery decrypts in place over pages the sender does not own -- an unprivileged page-cache write (the "Fragnesia" primitive). do_execute_actions() ignores output_userspace()'s return value, so any action after a failed USERSPACE upcall inherits the stripped skb. Move the skb_tx_error() to the flow-miss drop path - the "default" branch of ovs_dp_process_packet()'s switch(error), before kfree_skb(). The call has been here since commit 36d5fe6a0007 ("core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors") but was harmless until esp_input() began relying on SKBFL_SHARED_FRAG to gate in-place decrypt; only then did stripping it on a still-forwarded skb become a page-cache write primitive.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root Scorecard

References

8 references

URL	Tags
https://git.kernel.org/stable/c/5de5d554141a15b3f…
https://git.kernel.org/stable/c/48db11e115d1b232e…
https://git.kernel.org/stable/c/4477222e2916a18e2…
https://git.kernel.org/stable/c/4d5c460ef8754be1d…
https://git.kernel.org/stable/c/6767d70cf46f65807…
https://git.kernel.org/stable/c/e41a59fc056f63a7a…
https://git.kernel.org/stable/c/5d85eef222cfd28e7…
https://git.kernel.org/stable/c/0dbc2398fca3bb33e…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 5de5d554141a15b3f1f5c978fd9f7f4fd6d0600a (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 48db11e115d1b232edc5591604adc6eda95cd545 (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 4477222e2916a18e273edc139c955ade6bbb7a69 (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 4d5c460ef8754be1d43b16dbf02695b008b207d6 (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 6767d70cf46f65807a6a4c4406a518e6c12e36ae (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < e41a59fc056f63a7a1f42788913c53cc48d744aa (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 5d85eef222cfd28e73deed7402c100229e8b9e6e (git) Affected: 36d5fe6a000790f56039afe26834265db0a3ad4c , < 0dbc2398fca3bb33eda963849f865ddb1b3aa05e (git) Affected: c5f0c0e7525443add533495e93ba8de6feab2396 (git) Affected: 1674b4bf3eea3cac51b70778e89f8025f7cfe695 (git) Affected: 3.10.51 , < 3.11 (semver) Affected: 3.12.40 , < 3.13 (semver)
Linux	Linux	Affected: 3.14 Unaffected: 0 , < 3.14 (semver) Unaffected: 5.10.270 , ≤ 5.10.* (semver) Unaffected: 5.15.221 , ≤ 5.15.* (semver) Unaffected: 6.1.188 , ≤ 6.1.* (semver) Unaffected: 6.6.157 , ≤ 6.6.* (semver) Unaffected: 6.12.109 , ≤ 6.12.* (semver) Unaffected: 6.18.50 , ≤ 6.18.* (semver) Unaffected: 7.2.4 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/openvswitch/datapath.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5de5d554141a15b3f1f5c978fd9f7f4fd6d0600a",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "48db11e115d1b232edc5591604adc6eda95cd545",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "4477222e2916a18e273edc139c955ade6bbb7a69",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "4d5c460ef8754be1d43b16dbf02695b008b207d6",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "6767d70cf46f65807a6a4c4406a518e6c12e36ae",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "e41a59fc056f63a7a1f42788913c53cc48d744aa",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "5d85eef222cfd28e73deed7402c100229e8b9e6e",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "lessThan": "0dbc2398fca3bb33eda963849f865ddb1b3aa05e",
              "status": "affected",
              "version": "36d5fe6a000790f56039afe26834265db0a3ad4c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c5f0c0e7525443add533495e93ba8de6feab2396",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1674b4bf3eea3cac51b70778e89f8025f7cfe695",
              "versionType": "git"
            },
            {
              "lessThan": "3.11",
              "status": "affected",
              "version": "3.10.51",
              "versionType": "semver"
            },
            {
              "lessThan": "3.13",
              "status": "affected",
              "version": "3.12.40",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/openvswitch/datapath.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.14"
            },
            {
              "lessThan": "3.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.270",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.270",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.221",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.188",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.157",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.109",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "3.10.51",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "3.12.40",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: only skb_tx_error() a packet we are about to drop\n\nqueue_userspace_packet() borrows the packet skb -- it only copies it into\na private netlink message (user_skb) and does not own it; on return\ndo_execute_actions() keeps forwarding it through the flow\u0027s remaining\nactions. Its error path nevertheless calls skb_tx_error(skb), which via\nskb_zcopy_clear() does skb_shinfo(skb)-\u003eflags \u0026= ~SKBFL_ALL_ZEROCOPY,\nstripping SKBFL_SHARED_FRAG from that live skb (skb_tx_error()\u0027s kerneldoc\nsays \"skb must be freed afterwards\").\n\nFor a MSG_ZEROCOPY skb carrying page-cache frags, SKBFL_SHARED_FRAG is\nwhat makes esp_input() skb_cow_data() before in-place AEAD; once it is\nstripped a later local ESP-in-UDP delivery decrypts in place over pages\nthe sender does not own -- an unprivileged page-cache write (the\n\"Fragnesia\" primitive).\ndo_execute_actions() ignores output_userspace()\u0027s return value, so any\naction after a failed USERSPACE upcall inherits the stripped skb.\n\nMove the skb_tx_error() to the flow-miss drop path - the \"default\"\nbranch of ovs_dp_process_packet()\u0027s switch(error), before kfree_skb().\n\nThe call has been here since commit 36d5fe6a0007 (\"core, nfqueue,\nopenvswitch: Orphan frags in skb_zerocopy and handle errors\") but was\nharmless until esp_input() began relying on SKBFL_SHARED_FRAG to gate\nin-place decrypt; only then did stripping it on a still-forwarded skb\nbecome a page-cache write primitive."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The strip runs only on a locally originated MSG_ZEROCOPY skb that still has a zerocopy uarg (skb_zcopy_clear is a no-op otherwise); NIC-received packets never carry that uarg, and the later in-place ESP decrypt is via a local SA, so a local account is required.\nAC:L - The attacker fully controls the OVS flow (non-last USERSPACE with a PID that makes genlmsg_unicast fail), the MSG_ZEROCOPY send, and the ESP SA/payload; do_execute_actions() ignores the upcall error, so the shared-frag strip and in-place decrypt are deterministic with no race beyond attacker influence.\nPR:L - OVS genetlink families are netnsok and use GENL_UNS_ADMIN_PERM (CAP_NET_ADMIN in the socket user_ns); an unprivileged user can unshare -Urn, create a datapath/flow, enable SO_ZEROCOPY, and install xfrm SAs, while the global page cache remains the corruption target.\nUI:N - The attacker installs the OVS userspace-then-output flow, sends the MSG_ZEROCOPY packet, and completes local ESP-in-UDP delivery without any victim action such as opening a file or mounting a filesystem.\nS:U - The resulting page-cache write is a standard in-kernel memory-corruption/privilege-escalation primitive on the same host; it does not cross a VM hypervisor or IOMMU security boundary.\nC:H - Clearing SKBFL_SHARED_FRAG lets later esp_input() skip skb_cow_data() and AEAD-decrypt in place over page-cache-backed frags, a write primitive into globally cached file/code pages that can be leveraged for arbitrary disclosure.\nI:H - With the shared-frag marker stripped, ESP decrypts attacker-controlled plaintext in place over page-cache pages the sender does not own, yielding the Fragnesia unprivileged write into files the attacker could only read.\nA:H - In-place writes into page-cache-backed or still-mapped zerocopy pages corrupt shared kernel/file state and readily cause oopses, panics, and process crashes; skb_tx_error also completes the uarg while the skb is still in flight."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-14T12:00:22.434Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5de5d554141a15b3f1f5c978fd9f7f4fd6d0600a"
        },
        {
          "url": "https://git.kernel.org/stable/c/48db11e115d1b232edc5591604adc6eda95cd545"
        },
        {
          "url": "https://git.kernel.org/stable/c/4477222e2916a18e273edc139c955ade6bbb7a69"
        },
        {
          "url": "https://git.kernel.org/stable/c/4d5c460ef8754be1d43b16dbf02695b008b207d6"
        },
        {
          "url": "https://git.kernel.org/stable/c/6767d70cf46f65807a6a4c4406a518e6c12e36ae"
        },
        {
          "url": "https://git.kernel.org/stable/c/e41a59fc056f63a7a1f42788913c53cc48d744aa"
        },
        {
          "url": "https://git.kernel.org/stable/c/5d85eef222cfd28e73deed7402c100229e8b9e6e"
        },
        {
          "url": "https://git.kernel.org/stable/c/0dbc2398fca3bb33eda963849f865ddb1b3aa05e"
        }
      ],
      "title": "openvswitch: only skb_tx_error() a packet we are about to drop",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89487",
    "datePublished": "2026-09-11T19:43:40.776Z",
    "dateReserved": "2026-09-11T19:38:34.713Z",
    "dateUpdated": "2026-09-14T12:00:22.434Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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EUVD-2026-367596

CVE-2026-89487 (GCVE-0-2026-89487)

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