Vulnerability-Lookup

CVE-2026-47183 (GCVE-0-2026-47183)

Vulnerability from cvelistv5 – Published: 2026-07-17 18:22 – Updated: 2026-07-17 23:15

Title

Zeroconf: Unbounded exception-dedup state retains packet buffers via traceback frame locals, enabling LAN-local memory exhaustion

Summary

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.6, DNSIncoming._log_exception_debug and the four QuietLogger exception-dedup methods stored an unbounded _seen_logs dictionary keyed by attacker-influenced IncomingDecodeError messages, retaining sys.exc_info() tracebacks whose frame locals kept raw packet self.data buffers and allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to drive memory growth until mDNS-dependent features degrade or the process is OOM-killed. This issue is fixed in version 0.149.6.

Severity

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-400 - Uncontrolled Resource Consumption

Assigner

GitHub_M

References

5 references

URL	Tags
https://github.com/python-zeroconf/python-zerocon…	x_refsource_CONFIRM
https://github.com/python-zeroconf/python-zerocon…	x_refsource_MISC
https://github.com/python-zeroconf/python-zerocon…	x_refsource_MISC
https://github.com/python-zeroconf/python-zerocon…	x_refsource_MISC
https://github.com/python-zeroconf/python-zerocon…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
python-zeroconf	python-zeroconf	Affected: < 0.149.6

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-47183

Vulnerability from fkie_nvd - Published: 2026-07-17 19:17 - Updated: 2026-07-18 00:16

Severity

6.5 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/python-zeroconf/python-zeroconf/commit/95561e28b24922358f1991e38e3a86d70d72dcec
	security-advisories@github.com	https://github.com/python-zeroconf/python-zeroconf/issues/1714
	security-advisories@github.com	https://github.com/python-zeroconf/python-zeroconf/pull/1717
	security-advisories@github.com	https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.6
	security-advisories@github.com	https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-phvx-9mgw-67r5

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "python-zeroconf",
          "vendor": "python-zeroconf",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.149.6"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.6, DNSIncoming._log_exception_debug and the four QuietLogger exception-dedup methods stored an unbounded _seen_logs dictionary keyed by attacker-influenced IncomingDecodeError messages, retaining sys.exc_info() tracebacks whose frame locals kept raw packet self.data buffers and allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to drive memory growth until mDNS-dependent features degrade or the process is OOM-killed. This issue is fixed in version 0.149.6."
    }
  ],
  "id": "CVE-2026-47183",
  "lastModified": "2026-07-18T00:16:48.117",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
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        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
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    },
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    },
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GHSA-PHVX-9MGW-67R5

Vulnerability from github – Published: 2026-05-29 20:13 – Updated: 2026-05-29 20:13

Summary

zeroconf: Unbounded exception-dedup state retains packet buffers via traceback frame locals, enabling LAN-local memory exhaustion

Details

Impact

DNSIncoming._log_exception_debug and the four QuietLogger exception-dedup methods stored an unbounded _seen_logs dict keyed by str(sys.exc_info()[1]). The seven IncomingDecodeError messages raised from _read_name / _decode_labels_at_offset (RFC 6762 §18 name-decoding error paths) all embed self.source — the peer's ephemeral source port, varying per packet — plus byte offset and pointer link, so every attacker-influenced combination produced a fresh dedup key. The stored value was the full sys.exc_info() triple, whose traceback's frame locals retained self.data (the raw inbound packet, up to 8966 bytes per RFC 6762 §17). Each unique malformed packet therefore pinned ~9 KB until process exit.

Any unauthenticated host on the local link (UDP/5353, 224.0.0.251 / ff02::fb) can drive memory growth at line rate; that includes a guest on the same Wi-Fi, a compromised IoT device, or a container on a shared bridge. On memory-constrained deployments (Home Assistant on Raspberry-Pi-class hardware is the canonical victim) sustained traffic trivially OOM-kills the process, and mDNS-dependent features (HomeKit, Chromecast/Matter, AirPlay, printers) degrade or fail.

Patches

Fixed in zeroconf 0.149.6 (PR #1717). Upgrade to >= 0.149.6.

Workarounds

There is no in-process workaround; upgrading is the fix. Otherwise, restrict mDNS (UDP/5353) to trusted Layer-2 segments via AP client isolation, guest-network separation, or host firewall rules.

Resources

PR #1717, fix
Issue #1714, public tracking issue
RFC 6762 §17, RFC 6762 §18, CWE-400

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "zeroconf"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.149.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-47183"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-29T20:13:08Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\n`DNSIncoming._log_exception_debug` and the four `QuietLogger` exception-dedup methods stored an unbounded `_seen_logs` dict keyed by `str(sys.exc_info()[1])`. The seven `IncomingDecodeError` messages raised from `_read_name` / `_decode_labels_at_offset` (RFC 6762 \u00a718 name-decoding error paths) all embed `self.source` \u2014 the peer\u0027s ephemeral source port, varying per packet \u2014 plus byte `offset` and pointer `link`, so every attacker-influenced combination produced a fresh dedup key. The stored value was the full `sys.exc_info()` triple, whose traceback\u0027s frame locals retained `self.data` (the raw inbound packet, up to 8966 bytes per RFC 6762 \u00a717). Each unique malformed packet therefore pinned ~9 KB until process exit.\n\nAny unauthenticated host on the local link (UDP/5353, `224.0.0.251` / `ff02::fb`) can drive memory growth at line rate; that includes a guest on the same Wi-Fi, a compromised IoT device, or a container on a shared bridge. On memory-constrained deployments (Home Assistant on Raspberry-Pi-class hardware is the canonical victim) sustained traffic trivially OOM-kills the process, and mDNS-dependent features (HomeKit, Chromecast/Matter, AirPlay, printers) degrade or fail.\n\n### Patches\nFixed in `zeroconf` 0.149.6 ([PR #1717](https://github.com/python-zeroconf/python-zeroconf/pull/1717)). Upgrade to `\u003e= 0.149.6`.\n\n### Workarounds\nThere is no in-process workaround; upgrading is the fix. Otherwise, restrict mDNS (UDP/5353) to trusted Layer-2 segments via AP client isolation, guest-network separation, or host firewall rules.\n\n### Resources\n- [PR #1717](https://github.com/python-zeroconf/python-zeroconf/pull/1717), fix\n- [Issue #1714](https://github.com/python-zeroconf/python-zeroconf/issues/1714), public tracking issue\n- [RFC 6762 \u00a717](https://www.rfc-editor.org/rfc/rfc6762#section-17), [RFC 6762 \u00a718](https://www.rfc-editor.org/rfc/rfc6762#section-18), [CWE-400](https://cwe.mitre.org/data/definitions/400.html)",
  "id": "GHSA-phvx-9mgw-67r5",
  "modified": "2026-05-29T20:13:08Z",
  "published": "2026-05-29T20:13:08Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-phvx-9mgw-67r5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/issues/1714"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/pull/1717"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/python-zeroconf/python-zeroconf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "zeroconf: Unbounded exception-dedup state retains packet buffers via traceback frame locals, enabling LAN-local memory exhaustion"
}

PYSEC-2026-3437

Vulnerability from pysec - Published: 2026-07-13 15:19 - Updated: 2026-07-13 16:07

Details

Impact

Patches

Fixed in zeroconf 0.149.6 (PR #1717). Upgrade to >= 0.149.6.

Workarounds

There is no in-process workaround; upgrading is the fix. Otherwise, restrict mDNS (UDP/5353) to trusted Layer-2 segments via AP client isolation, guest-network separation, or host firewall rules.

Resources

PR #1717, fix
Issue #1714, public tracking issue
RFC 6762 §17, RFC 6762 §18, CWE-400

Severity

6.5 (Medium)


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

Impacted products

Name	purl
zeroconf	pkg:pypi/zeroconf

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "zeroconf",
        "purl": "pkg:pypi/zeroconf"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.149.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.100.0",
        "0.101.0",
        "0.102.0",
        "0.103.0",
        "0.104.0",
        "0.105.0",
        "0.106.0",
        "0.107.0",
        "0.108.0",
        "0.109.0",
        "0.110.0",
        "0.111.0",
        "0.112.0",
        "0.114.0",
        "0.115.0",
        "0.115.1",
        "0.115.2",
        "0.116.0",
        "0.117.0",
        "0.118.0",
        "0.118.1",
        "0.119.0",
        "0.120.0",
        "0.121.0",
        "0.122.0",
        "0.122.1",
        "0.122.2",
        "0.122.3",
        "0.123.0",
        "0.124.0",
        "0.125.0",
        "0.126.0",
        "0.127.0",
        "0.128.0",
        "0.128.1",
        "0.128.2",
        "0.128.3",
        "0.128.4",
        "0.128.5",
        "0.129.0",
        "0.130.0",
        "0.131.0",
        "0.132.0",
        "0.132.1",
        "0.132.2",
        "0.133.0",
        "0.134.0",
        "0.135.0",
        "0.136.0",
        "0.136.1",
        "0.136.2",
        "0.137.0",
        "0.137.1",
        "0.137.2",
        "0.138.0",
        "0.138.1",
        "0.139.0",
        "0.14",
        "0.140.0",
        "0.140.1",
        "0.141.0",
        "0.142.0",
        "0.143.0",
        "0.143.1",
        "0.144.0",
        "0.144.1",
        "0.144.2",
        "0.144.3",
        "0.145.0",
        "0.145.1",
        "0.146.0",
        "0.146.1",
        "0.146.2",
        "0.146.3",
        "0.146.4",
        "0.146.5",
        "0.147.0",
        "0.147.1",
        "0.147.2",
        "0.147.3",
        "0.147.4",
        "0.148.0",
        "0.149.0",
        "0.149.1",
        "0.149.2",
        "0.149.3",
        "0.149.4",
        "0.149.5",
        "0.15",
        "0.15.1",
        "0.16.0",
        "0.17.0",
        "0.17.1",
        "0.17.2",
        "0.17.3",
        "0.17.4",
        "0.17.5",
        "0.17.6",
        "0.17.7",
        "0.18.0",
        "0.19.0",
        "0.19.1",
        "0.20.0",
        "0.21.0",
        "0.21.1",
        "0.21.2",
        "0.21.3",
        "0.22.0",
        "0.23.0",
        "0.24.0",
        "0.24.1",
        "0.24.2",
        "0.24.3",
        "0.24.4",
        "0.24.5",
        "0.25.0",
        "0.25.1",
        "0.26.0",
        "0.26.1",
        "0.26.2",
        "0.26.3",
        "0.27.0",
        "0.27.1",
        "0.28.0",
        "0.28.1",
        "0.28.2",
        "0.28.3",
        "0.28.4",
        "0.28.5",
        "0.28.6",
        "0.28.7",
        "0.28.8",
        "0.29.0",
        "0.30.0",
        "0.31.0",
        "0.32.0",
        "0.32.1",
        "0.33.0",
        "0.33.1",
        "0.33.2",
        "0.33.3",
        "0.33.4",
        "0.34.0",
        "0.34.1",
        "0.34.2",
        "0.34.3",
        "0.35.0",
        "0.35.1",
        "0.36.0",
        "0.36.1",
        "0.36.11",
        "0.36.12",
        "0.36.13",
        "0.36.2",
        "0.36.3",
        "0.36.4",
        "0.36.5",
        "0.36.6",
        "0.36.7",
        "0.36.8",
        "0.36.9",
        "0.37.0",
        "0.38.0",
        "0.38.1",
        "0.38.3",
        "0.38.4",
        "0.38.5",
        "0.38.6",
        "0.38.7",
        "0.39.0",
        "0.39.1",
        "0.39.2",
        "0.39.3",
        "0.39.4",
        "0.43.0",
        "0.44.0",
        "0.45.0",
        "0.46.0",
        "0.47.0",
        "0.47.1",
        "0.47.2",
        "0.47.3",
        "0.47.4",
        "0.48.0",
        "0.49.0",
        "0.50.0",
        "0.51.0",
        "0.52.0",
        "0.53.0",
        "0.53.1",
        "0.54.0",
        "0.55.0",
        "0.56.0",
        "0.57.0",
        "0.58.0",
        "0.58.1",
        "0.58.2",
        "0.59.0",
        "0.60.0",
        "0.61.0",
        "0.62.0",
        "0.63.0",
        "0.64.0",
        "0.64.1",
        "0.65.0",
        "0.66.0",
        "0.67.0",
        "0.68.0",
        "0.68.1",
        "0.69.0",
        "0.70.0",
        "0.71.0",
        "0.71.1",
        "0.71.2",
        "0.71.3",
        "0.71.4",
        "0.71.5",
        "0.72.0",
        "0.72.1",
        "0.72.2",
        "0.72.3",
        "0.73.0",
        "0.74.0",
        "0.75.0",
        "0.76.0",
        "0.77.0",
        "0.78.0",
        "0.79.0",
        "0.80.0",
        "0.81.0",
        "0.82.0",
        "0.82.1",
        "0.83.0",
        "0.83.1",
        "0.84.0",
        "0.85.0",
        "0.86.0",
        "0.87.0",
        "0.88.0",
        "0.89.0",
        "0.90.0",
        "0.91.0",
        "0.91.1",
        "0.92.0",
        "0.93.0",
        "0.93.1",
        "0.94.0",
        "0.95.0",
        "0.96.0",
        "0.97.0",
        "0.98.0",
        "0.99.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-47183",
    "GHSA-phvx-9mgw-67r5"
  ],
  "details": "### Impact\n`DNSIncoming._log_exception_debug` and the four `QuietLogger` exception-dedup methods stored an unbounded `_seen_logs` dict keyed by `str(sys.exc_info()[1])`. The seven `IncomingDecodeError` messages raised from `_read_name` / `_decode_labels_at_offset` (RFC 6762 \u00a718 name-decoding error paths) all embed `self.source` \u2014 the peer\u0027s ephemeral source port, varying per packet \u2014 plus byte `offset` and pointer `link`, so every attacker-influenced combination produced a fresh dedup key. The stored value was the full `sys.exc_info()` triple, whose traceback\u0027s frame locals retained `self.data` (the raw inbound packet, up to 8966 bytes per RFC 6762 \u00a717). Each unique malformed packet therefore pinned ~9 KB until process exit.\n\nAny unauthenticated host on the local link (UDP/5353, `224.0.0.251` / `ff02::fb`) can drive memory growth at line rate; that includes a guest on the same Wi-Fi, a compromised IoT device, or a container on a shared bridge. On memory-constrained deployments (Home Assistant on Raspberry-Pi-class hardware is the canonical victim) sustained traffic trivially OOM-kills the process, and mDNS-dependent features (HomeKit, Chromecast/Matter, AirPlay, printers) degrade or fail.\n\n### Patches\nFixed in `zeroconf` 0.149.6 ([PR #1717](https://github.com/python-zeroconf/python-zeroconf/pull/1717)). Upgrade to `\u003e= 0.149.6`.\n\n### Workarounds\nThere is no in-process workaround; upgrading is the fix. Otherwise, restrict mDNS (UDP/5353) to trusted Layer-2 segments via AP client isolation, guest-network separation, or host firewall rules.\n\n### Resources\n- [PR #1717](https://github.com/python-zeroconf/python-zeroconf/pull/1717), fix\n- [Issue #1714](https://github.com/python-zeroconf/python-zeroconf/issues/1714), public tracking issue\n- [RFC 6762 \u00a717](https://www.rfc-editor.org/rfc/rfc6762#section-17), [RFC 6762 \u00a718](https://www.rfc-editor.org/rfc/rfc6762#section-18), [CWE-400](https://cwe.mitre.org/data/definitions/400.html)",
  "id": "PYSEC-2026-3437",
  "modified": "2026-07-13T16:07:36.920004Z",
  "published": "2026-07-13T15:19:14.609273Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-phvx-9mgw-67r5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/issues/1714"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-zeroconf/python-zeroconf/pull/1717"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/python-zeroconf/python-zeroconf"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/zeroconf"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-phvx-9mgw-67r5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47183"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "zeroconf: Unbounded exception-dedup state retains packet buffers via traceback frame locals, enabling LAN-local memory exhaustion"
}

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.

Action not permitted

CVE-2026-47183 (GCVE-0-2026-47183)

FKIE_CVE-2026-47183

GHSA-PHVX-9MGW-67R5

Impact

Patches

Workarounds

Resources

PYSEC-2026-3437

Impact

Patches

Workarounds

Resources

Tags

Sightings

Nomenclature