CVE-2026-10638 (GCVE-0-2026-10638)

Vulnerability from cvelistv5 – Published: 2026-06-16 13:16 – Updated: 2026-10-15 22:10
VLAI
Title
Use-after-free in Zephyr ICMPv6 RX path when updating statistics after sending an echo reply or error
Summary
subsys/net/ip/icmpv6.c reads the network interface from a net_pkt after that packet has been handed to net_try_send_data(). In icmpv6_handle_echo_request() and net_icmpv6_send_error(), the post-send statistics update calls net_pkt_iface(reply)/net_pkt_iface(pkt) on the just-sent packet. The send path (net_try_send_data -> net_if_tx) unreferences and may free the packet back to its memory slab before returning — synchronously in the RX thread when no TX queue is configured (CONFIG_NET_TC_TX_COUNT == 0), and asynchronously the driver/L2 may already have freed it otherwise. net_pkt_iface() therefore dereferences a freed (and possibly reused) net_pkt; with CONFIG_NET_STATISTICS_PER_INTERFACE the stale iface pointer is further dereferenced and written through (iface->stats.icmp.sent++), turning the use-after-free read into a write through an attacker-influenceable pointer. The core stack already documents this hazard in net_core.c ("do not use pkt after that call") and caches iface before sending; the ICMPv6 callers did not. An unauthenticated remote attacker triggers the flaw simply by sending an ICMPv6 Echo Request (ping) or an IPv6 packet that elicits an ICMPv6 error (unknown next header, fragment reassembly timeout, destination unreachable), leading to denial of service via crash and potential memory corruption. Affected: Zephyr networking with CONFIG_NET_NATIVE_IPV6, roughly v4.2.0 through v4.4.0. The fix caches the interface pointer before sending and uses it for all statistics updates; the sibling commit 86e21665d46 fixes the identical bug in ICMPv4.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-16 15:29 UTC
CWE
Assigner
zephyr CNA under the mitre root
CNA scorecard B 77/100 over 200 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
zephyrproject zephyr Affected: 3.7.0 , < 4.3.1 (semver)
Affected: 4.4.0 , < 4.4.1 (semver)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-10638",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T15:29:46.610373Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-16T15:29:52.743Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "defaultStatus": "unaffected",
          "packageName": "zephyr",
          "product": "zephyr",
          "programFiles": [
            "subsys/net/ip/icmpv6.c"
          ],
          "vendor": "zephyrproject",
          "versions": [
            {
              "lessThan": "4.3.1",
              "status": "affected",
              "version": "3.7.0",
              "versionType": "semver"
            },
            {
              "lessThan": "4.4.1",
              "status": "affected",
              "version": "4.4.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "subsys/net/ip/icmpv6.c reads the network interface from a net_pkt after that packet has been handed to net_try_send_data(). In icmpv6_handle_echo_request() and net_icmpv6_send_error(), the post-send statistics update calls net_pkt_iface(reply)/net_pkt_iface(pkt) on the just-sent packet.\n\nThe send path (net_try_send_data -\u003e net_if_tx) unreferences and may free the packet back to its memory slab before returning \u2014 synchronously in the RX thread when no TX queue is configured (CONFIG_NET_TC_TX_COUNT == 0), and asynchronously the driver/L2 may already have freed it otherwise. net_pkt_iface() therefore dereferences a freed (and possibly reused) net_pkt; with CONFIG_NET_STATISTICS_PER_INTERFACE the stale iface pointer is further dereferenced and written through (iface-\u003estats.icmp.sent++), turning the use-after-free read into a write through an attacker-influenceable pointer.\n\nThe core stack already documents this hazard in net_core.c (\"do not use pkt after that call\") and caches iface before sending; the ICMPv6 callers did not.\n\nAn unauthenticated remote attacker triggers the flaw simply by sending an ICMPv6 Echo Request (ping) or an IPv6 packet that elicits an ICMPv6 error (unknown next header, fragment reassembly timeout, destination unreachable), leading to denial of service via crash and potential memory corruption. Affected: Zephyr networking with CONFIG_NET_NATIVE_IPV6, roughly v4.2.0 through v4.4.0.\n\nThe fix caches the interface pointer before sending and uses it for all statistics updates; the sibling commit 86e21665d46 fixes the identical bug in ICMPv4."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-416",
              "description": "use-after-free",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-15T22:10:01.553Z",
        "orgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
        "shortName": "zephyr"
      },
      "references": [
        {
          "name": "Fix commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/zephyrproject-rtos/zephyr/commit/09c8578c66b517c5165cde53332ed5d8d8ef2cfc"
        },
        {
          "name": "GHSA-m92g-94xv-wvw2",
          "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-m92g-94xv-wvw2"
        }
      ],
      "title": "Use-after-free in Zephyr ICMPv6 RX path when updating statistics after sending an echo reply or error",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
    "assignerShortName": "zephyr",
    "cveId": "CVE-2026-10638",
    "datePublished": "2026-06-16T13:16:14.688Z",
    "dateReserved": "2026-06-02T15:10:55.949Z",
    "dateUpdated": "2026-10-15T22:10:01.553Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-10638",
      "date": "2026-10-27",
      "epss": "0.00352",
      "percentile": "0.28719"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
                "defaultStatus": "unaffected",
                "packageName": "zephyr",
                "product": "zephyr",
                "programFiles": [
                  "subsys/net/ip/icmpv6.c"
                ],
                "vendor": "zephyrproject",
                "versions": [
                  {
                    "lessThan": "4.3.1",
                    "status": "affected",
                    "version": "3.7.0",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "4.4.1",
                    "status": "affected",
                    "version": "4.4.0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "vulnerabilities@zephyrproject.org"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "B4B6E024-A0B6-48E0-A4F6-FF276949270A",
                    "versionEndExcluding": "4.5.0",
                    "versionStartIncluding": "4.2.0",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "subsys/net/ip/icmpv6.c reads the network interface from a net_pkt after that packet has been handed to net_try_send_data(). In icmpv6_handle_echo_request() and net_icmpv6_send_error(), the post-send statistics update calls net_pkt_iface(reply)/net_pkt_iface(pkt) on the just-sent packet.\n\nThe send path (net_try_send_data -\u003e net_if_tx) unreferences and may free the packet back to its memory slab before returning \u2014 synchronously in the RX thread when no TX queue is configured (CONFIG_NET_TC_TX_COUNT == 0), and asynchronously the driver/L2 may already have freed it otherwise. net_pkt_iface() therefore dereferences a freed (and possibly reused) net_pkt; with CONFIG_NET_STATISTICS_PER_INTERFACE the stale iface pointer is further dereferenced and written through (iface-\u003estats.icmp.sent++), turning the use-after-free read into a write through an attacker-influenceable pointer.\n\nThe core stack already documents this hazard in net_core.c (\"do not use pkt after that call\") and caches iface before sending; the ICMPv6 callers did not.\n\nAn unauthenticated remote attacker triggers the flaw simply by sending an ICMPv6 Echo Request (ping) or an IPv6 packet that elicits an ICMPv6 error (unknown next header, fragment reassembly timeout, destination unreachable), leading to denial of service via crash and potential memory corruption. Affected: Zephyr networking with CONFIG_NET_NATIVE_IPV6, roughly v4.2.0 through v4.4.0.\n\nThe fix caches the interface pointer before sending and uses it for all statistics updates; the sibling commit 86e21665d46 fixes the identical bug in ICMPv4."
          },
          {
            "lang": "es",
            "value": "subsys/net/ip/icmpv6.c lee la interfaz de red de un net_pkt despu\u00e9s de que ese paquete ha sido entregado a net_try_send_data(). En icmpv6_handle_echo_request() y net_icmpv6_send_error(), la actualizaci\u00f3n de estad\u00edsticas post-env\u00edo llama a net_pkt_iface(reply)/net_pkt_iface(pkt) en el paquete reci\u00e9n enviado. La ruta de env\u00edo (net_try_send_data - net_if_tx) desreferencia y puede liberar el paquete de vuelta a su bloque de memoria antes de regresar - sincr\u00f3nicamente en el hilo RX cuando no hay cola TX configurada (CONFIG_NET_TC_TX_COUNT == 0), y asincr\u00f3nicamente el controlador/L2 puede ya haberlo liberado de otra manera. net_pkt_iface() por lo tanto desreferencia un net_pkt liberado (y posiblemente reutilizado); con CONFIG_NET_STATISTICS_PER_INTERFACE el puntero iface obsoleto es desreferenciado y escrito a trav\u00e9s (iface-stats.icmp.sent++), convirtiendo la lectura de uso despu\u00e9s de liberaci\u00f3n en una escritura a trav\u00e9s de un puntero influenciable por el atacante. La pila central ya documenta este peligro en net_core.c (\u2019no usar pkt despu\u00e9s de esa llamada\u2019) y almacena en cach\u00e9 iface antes de enviar; los llamadores de ICMPv6 no lo hicieron. Un atacante remoto no autenticado activa la falla simplemente enviando una solicitud de eco ICMPv6 (ping) o un paquete IPv6 que provoca un error ICMPv6 (encabezado siguiente desconocido, tiempo de espera de reensamblaje de fragmentos, destino inalcanzable), lo que lleva a denegaci\u00f3n de servicio a trav\u00e9s de un fallo y potencial corrupci\u00f3n de memoria. Afectado: redes Zephyr con CONFIG_NET_NATIVE_IPV6, aproximadamente de v4.2.0 a v4.4.0. La soluci\u00f3n almacena en cach\u00e9 el puntero de interfaz antes de enviar y lo usa para todas las actualizaciones de estad\u00edsticas; el commit hermano 86e21665d46 corrige el error id\u00e9ntico en ICMPv4."
          }
        ],
        "id": "CVE-2026-10638",
        "lastModified": "2026-10-26T12:10:00.130",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "HIGH",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 5.9,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.2,
              "impactScore": 3.6,
              "source": "vulnerabilities@zephyrproject.org",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-10638",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T15:29:46.610373Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-06-16T15:16:34.097",
        "references": [
          {
            "source": "vulnerabilities@zephyrproject.org",
            "tags": [
              "Patch"
            ],
            "url": "https://github.com/zephyrproject-rtos/zephyr/commit/09c8578c66b517c5165cde53332ed5d8d8ef2cfc"
          },
          {
            "source": "vulnerabilities@zephyrproject.org",
            "tags": [
              "Broken Link"
            ],
            "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-m92g-94xv-wvw2"
          }
        ],
        "sourceIdentifier": "vulnerabilities@zephyrproject.org",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-416"
              }
            ],
            "source": "vulnerabilities@zephyrproject.org",
            "type": "Secondary"
          }
        ]
      }
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-10638",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-06-16T15:29:46.610373Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-06-16T15:29:49.895Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
              "defaultStatus": "unaffected",
              "packageName": "zephyr",
              "product": "zephyr",
              "programFiles": [
                "subsys/net/ip/icmpv6.c"
              ],
              "vendor": "zephyrproject",
              "versions": [
                {
                  "lessThan": "4.5.0",
                  "status": "affected",
                  "version": "3.7.0",
                  "versionType": "semver"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "subsys/net/ip/icmpv6.c reads the network interface from a net_pkt after that packet has been handed to net_try_send_data(). In icmpv6_handle_echo_request() and net_icmpv6_send_error(), the post-send statistics update calls net_pkt_iface(reply)/net_pkt_iface(pkt) on the just-sent packet.\n\nThe send path (net_try_send_data -\u003e net_if_tx) unreferences and may free the packet back to its memory slab before returning \u2014 synchronously in the RX thread when no TX queue is configured (CONFIG_NET_TC_TX_COUNT == 0), and asynchronously the driver/L2 may already have freed it otherwise. net_pkt_iface() therefore dereferences a freed (and possibly reused) net_pkt; with CONFIG_NET_STATISTICS_PER_INTERFACE the stale iface pointer is further dereferenced and written through (iface-\u003estats.icmp.sent++), turning the use-after-free read into a write through an attacker-influenceable pointer.\n\nThe core stack already documents this hazard in net_core.c (\"do not use pkt after that call\") and caches iface before sending; the ICMPv6 callers did not.\n\nAn unauthenticated remote attacker triggers the flaw simply by sending an ICMPv6 Echo Request (ping) or an IPv6 packet that elicits an ICMPv6 error (unknown next header, fragment reassembly timeout, destination unreachable), leading to denial of service via crash and potential memory corruption. Affected: Zephyr networking with CONFIG_NET_NATIVE_IPV6, roughly v4.2.0 through v4.4.0.\n\nThe fix caches the interface pointer before sending and uses it for all statistics updates; the sibling commit 86e21665d46 fixes the identical bug in ICMPv4."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 5.9,
                "baseSeverity": "MEDIUM",
                "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "format": "CVSS"
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-416",
                  "description": "use-after-free",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-07-17T22:11:32.345Z",
            "orgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
            "shortName": "zephyr"
          },
          "references": [
            {
              "name": "Fix commit",
              "tags": [
                "patch"
              ],
              "url": "https://github.com/zephyrproject-rtos/zephyr/commit/09c8578c66b517c5165cde53332ed5d8d8ef2cfc"
            },
            {
              "name": "GHSA-m92g-94xv-wvw2",
              "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-m92g-94xv-wvw2"
            }
          ],
          "title": "Use-after-free in Zephyr ICMPv6 RX path when updating statistics after sending an echo reply or error",
          "x_generator": {
            "engine": "cvelib 1.8.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
        "assignerShortName": "zephyr",
        "cveId": "CVE-2026-10638",
        "datePublished": "2026-06-16T13:16:14.688Z",
        "dateReserved": "2026-06-02T15:10:55.949Z",
        "dateUpdated": "2026-07-17T22:11:32.345Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.