CVE-2026-80520 (GCVE-0-2026-80520)

Vulnerability from cvelistv5 – Published: 2026-08-26 14:37 – Updated: 2026-08-27 05:01
VLAI
Title
ovpn: fix NULL dereference when killing missing key
Summary
In the Linux kernel, the following vulnerability has been resolved: ovpn: fix NULL dereference when killing missing key ovpn_crypto_kill_key assumes both crypto slots are populated and dereferences each slot before checking it. That is not guaranteed: a peer can have only one installed key, and the kill path may be asked to remove a key that is not present. Read each slot once while holding the crypto state lock, check for NULL before looking at key_id, and only replace the slot that actually matches.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 89d3c0e4612afa1c6429ed68d298e35592fbe208 , < a47a080d06ee9d94dc6a2da0fc2b9beeeedb92b3 (git)
Affected: 89d3c0e4612afa1c6429ed68d298e35592fbe208 , < acf32a5dff082044cf0fd9492f3c10b7357c15ee (git)
Affected: 89d3c0e4612afa1c6429ed68d298e35592fbe208 , < 41d44ac7a61e2f74453af40d4fe1b82af9ea0ada (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.46 , ≤ 6.18.* (semver)
Unaffected: 7.1.10 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ovpn/crypto.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a47a080d06ee9d94dc6a2da0fc2b9beeeedb92b3",
              "status": "affected",
              "version": "89d3c0e4612afa1c6429ed68d298e35592fbe208",
              "versionType": "git"
            },
            {
              "lessThan": "acf32a5dff082044cf0fd9492f3c10b7357c15ee",
              "status": "affected",
              "version": "89d3c0e4612afa1c6429ed68d298e35592fbe208",
              "versionType": "git"
            },
            {
              "lessThan": "41d44ac7a61e2f74453af40d4fe1b82af9ea0ada",
              "status": "affected",
              "version": "89d3c0e4612afa1c6429ed68d298e35592fbe208",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ovpn/crypto.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.46",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.10",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\novpn: fix NULL dereference when killing missing key\n\novpn_crypto_kill_key assumes both crypto slots are populated and\ndereferences each slot before checking it. That is not guaranteed: a\npeer can have only one installed key, and the kill path may be asked to\nremove a key that is not present.\n\nRead each slot once while holding the crypto state lock, check for NULL\nbefore looking at key_id, and only replace the slot that actually\nmatches."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The bug is reached from ovpn_encrypt_post during outbound VPN encryption over UDP/TCP; a remote authenticated OpenVPN peer can drive high-volume tunnel traffic that exhausts packet IDs and triggers ovpn_crypto_kill_key on internet-facing VPN concentrators.\nAC:L - After a normal rekey leaves one key in slots[1] with slots[0] NULL, IV exhaustion deterministically calls ovpn_crypto_kill_key and the NULL dereference is reliable; a remote peer can sustain the encrypted traffic needed to reach the 32-bit packet-ID limit.\nPR:N - Exploitation requires only an established OpenVPN data-channel session to an ovpn-offloaded interface, not local shell access, CAP_NET_ADMIN, or init-namespace root; no kernel configuration privileges are needed beyond being a connected VPN peer.\nUI:N - Triggering IV exhaustion and the subsequent key-kill path requires no victim user interaction beyond routine automated VPN traffic and key rotation already performed by the tunnel daemon.\nS:U - Impact is a kernel NULL-pointer fault and denial of service within the kernel network stack; it does not cross a security boundary such as guest-to-host escape or sandbox breakout.\nC:N - This is a pure NULL pointer dereference when reading key_id from an unpopulated crypto slot; it does not expose kernel memory, leak pointers, or provide an arbitrary read primitive.\nI:N - The fault occurs on a NULL slot lookup and does not corrupt memory or enable arbitrary writes, code execution, or control-flow hijacking beyond the immediate crash.\nA:H - The NULL dereference in ovpn_crypto_kill_key causes a kernel oops or panic when IV exhaustion triggers the key-kill path, fully denying service to the host and all VPN peers on that node."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-27T05:01:16.637Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a47a080d06ee9d94dc6a2da0fc2b9beeeedb92b3"
        },
        {
          "url": "https://git.kernel.org/stable/c/acf32a5dff082044cf0fd9492f3c10b7357c15ee"
        },
        {
          "url": "https://git.kernel.org/stable/c/41d44ac7a61e2f74453af40d4fe1b82af9ea0ada"
        }
      ],
      "title": "ovpn: fix NULL dereference when killing missing key",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80520",
    "datePublished": "2026-08-26T14:37:01.983Z",
    "dateReserved": "2026-08-26T14:34:25.763Z",
    "dateUpdated": "2026-08-27T05:01:16.637Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-80520",
      "date": "2026-09-01",
      "epss": "0.00432",
      "percentile": "0.36027"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-80520\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-26T15:17:05.553\",\"lastModified\":\"2026-08-27T06:17:30.450\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\novpn: fix NULL dereference when killing missing key\\n\\novpn_crypto_kill_key assumes both crypto slots are populated and\\ndereferences each slot before checking it. That is not guaranteed: a\\npeer can have only one installed key, and the kill path may be asked to\\nremove a key that is not present.\\n\\nRead each slot once while holding the crypto state lock, check for NULL\\nbefore looking at key_id, and only replace the slot that actually\\nmatches.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/net/ovpn/crypto.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"89d3c0e4612afa1c6429ed68d298e35592fbe208\",\"lessThan\":\"a47a080d06ee9d94dc6a2da0fc2b9beeeedb92b3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"89d3c0e4612afa1c6429ed68d298e35592fbe208\",\"lessThan\":\"acf32a5dff082044cf0fd9492f3c10b7357c15ee\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"89d3c0e4612afa1c6429ed68d298e35592fbe208\",\"lessThan\":\"41d44ac7a61e2f74453af40d4fe1b82af9ea0ada\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/net/ovpn/crypto.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.16\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.16\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.46\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.10\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/41d44ac7a61e2f74453af40d4fe1b82af9ea0ada\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a47a080d06ee9d94dc6a2da0fc2b9beeeedb92b3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/acf32a5dff082044cf0fd9492f3c10b7357c15ee\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-27T10:55:24+00:00",
      "cve": "CVE-2026-80520",
      "id": "CVE-2026-80520",
      "initial_release_date": "2026-08-26T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ovpn: fix NULL dereference when killing missing key",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80520.json",
      "version": "3"
    }
  }
}



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.