Vulnerability-Lookup

GHSA-5PPH-8C9P-W8P3

Vulnerability from github – Published: 2026-10-21 15:42 – Updated: 2026-10-21 18:33

Details

Uncontrolled recursion in the mcpack2pb component in Apache bRPC (version < 1.18.0) on all platforms allows remote attackers to make the server crash via sending deeply nested mcpack data.

Root Cause: The bRPC mcpack2pb parser (used to serve nshead_mcpack / ubrpc / public_pbrpc requests) recursively parses nested objects and arrays without any depth limit. For a protobuf message that references itself (e.g. a repeated message field), the generated parser recurses once per nesting level of the incoming mcpack object. A deeply nested request makes the recursion grow unbounded, overflow the stack and crash the process.

Affected Scenarios: Use bRPC server with a recursive-schema protobuf message to serve nshead_mcpack / ubrpc / public_pbrpc requests from untrusted network.

How to Fix: (Choose one of the following options) 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3499

Note: No matter which option you choose, you should know that the fix enforces the documented parsing depth limit MAX_DEPTH (128) on the parse path, the same limit the serializer already applies. If your requests contain mcpack messages nested deeper than 128 levels, the request will be failed after applying the fix.

Severity

7.5 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-82230"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
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    "nvd_published_at": "2026-10-21T13:20:02Z",
    "severity": "HIGH"
  },
  "details": "Uncontrolled recursion in the mcpack2pb component in Apache bRPC (version \u003c 1.18.0) on all platforms allows remote attackers to make the server crash via sending deeply nested mcpack data.\n\nRoot Cause:\nThe bRPC mcpack2pb parser (used to serve nshead_mcpack / ubrpc / public_pbrpc requests) recursively parses nested objects and arrays without any depth limit. For a protobuf message that references itself (e.g. a repeated message field), the generated parser recurses once per nesting level of the incoming mcpack object. A deeply nested request makes the recursion grow unbounded, overflow the stack and crash the process.\n\nAffected Scenarios:\nUse bRPC server with a recursive-schema protobuf message to serve nshead_mcpack / ubrpc / public_pbrpc requests from untrusted network.\n\nHow to Fix:\n(Choose one of the following options)\n1. Upgrade bRPC to version 1.18.0, which fixes this issue.\n2. Apply this patch: https://github.com/apache/brpc/pull/3499\n\nNote:\nNo matter which option you choose, you should know that the fix enforces the documented parsing depth limit MAX_DEPTH (128) on the parse path, the same limit the serializer already applies. If your requests contain mcpack messages nested deeper than 128 levels, the request will be failed after applying the fix.",
  "id": "GHSA-5pph-8c9p-w8p3",
  "modified": "2026-10-21T18:33:15Z",
  "published": "2026-10-21T15:42:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-82230"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-82230 (GCVE-0-2026-82230)

Vulnerability from cvelistv5 – Published: 2026-10-21 12:03 – Updated: 2026-10-21 15:11

Title

Apache bRPC: Stack Exhaustion via Unbounded Recursion in mcpack2pb Parser

Summary

Uncontrolled recursion in the mcpack2pb component in Apache bRPC (version < 1.18.0) on all platforms allows remote attackers to make the server crash via sending deeply nested mcpack data. Root Cause: The bRPC mcpack2pb parser (used to serve nshead_mcpack / ubrpc / public_pbrpc requests) recursively parses nested objects and arrays without any depth limit. For a protobuf message that references itself (e.g. a repeated message field), the generated parser recurses once per nesting level of the incoming mcpack object. A deeply nested request makes the recursion grow unbounded, overflow the stack and crash the process. Affected Scenarios: Use bRPC server with a recursive-schema protobuf message to serve nshead_mcpack / ubrpc / public_pbrpc requests from untrusted network. How to Fix: (Choose one of the following options) 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3499 Note: No matter which option you choose, you should know that the fix enforces the documented parsing depth limit MAX_DEPTH (128) on the parse path, the same limit the serializer already applies. If your requests contain mcpack messages nested deeper than 128 levels, the request will be failed after applying the fix.

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-21 15:11 UTC

CWE

CWE-674 - Uncontrolled Recursion

Assigner

apache CNA under the mitre root

CNA scorecard B 76/100 over 1086 records in the last 180 days details

References

1 reference

URL	Tags
https://lists.apache.org/thread/2pf15ojj0vr7rtx95…	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache bRPC	Affected: 0 , < 1.18.0 (semver)

Credits

Kaixuan Li

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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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.

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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.
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