Vulnerability-Lookup

GHSA-P2GH-CFQ4-4WJC

Vulnerability from github – Published: 2026-03-25 21:02 – Updated: 2026-04-16 22:59

Summary

Protobuf: Denial of Service issue through malicious messages containing negative varints or deep recursion

Details

Impact

A Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured messages—specifically those containing negative varints or deep recursion—can be used to crash the application, impacting service availability.

Patches

Patches have been released to 5.34.0-RC1 and 4.33.6.

Severity ?

7.1 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "google/protobuf"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.33.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-6409"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-25T21:02:08Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\nA Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured messages\u2014specifically those containing negative `varint`s or deep recursion\u2014can be used to crash the application, impacting service availability.\n\n### Patches\nPatches have been released to 5.34.0-RC1 and 4.33.6.",
  "id": "GHSA-p2gh-cfq4-4wjc",
  "modified": "2026-04-16T22:59:37Z",
  "published": "2026-03-25T21:02:08Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/protocolbuffers/protobuf/security/advisories/GHSA-p2gh-cfq4-4wjc"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6409"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protocolbuffers/protobuf/issues/24159"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protocolbuffers/protobuf/issues/25067"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protocolbuffers/protobuf/commit/60e93d2d104f2af9cd345b1c6f3891d91430244a"
    },
    {
      "type": "WEB",
      "url": "https://github.com/protocolbuffers/protobuf/commit/c8e9b27d95c6ab2d0668b5889e7dac2c477b7038"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/protocolbuffers/protobuf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Protobuf: Denial of Service issue through malicious messages containing negative varints or deep recursion"
}

CVE-2026-6409 (GCVE-0-2026-6409)

Vulnerability from cvelistv5 – Published: 2026-04-16 14:30 – Updated: 2026-04-16 15:24

Title

Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input

Summary

A Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured messages—specifically those containing negative varints or deep recursion—can be used to crash the application, impacting service availability.

Severity ?

7.1 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE

CWE-20 - Improper input validation

Assigner

Google

References

URL

Tags

https://github.com/protocolbuffers/protobuf/secur…

Impacted products

	Vendor	Product	Version
	Protocol Buffers	Protobuf-php (Pecl)	Affected: 0 , < 5.34.0-RC1 (semver) Affected: 0 , < 4.33.6 (semver)

Credits

https://github.com/34selen

Show details on NVD website

JSON

To clipboard

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                "timestamp": "2026-04-16T15:23:55.455444Z",
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Sightings

Author	Source	Type	Date

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.

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