Vulnerability-Lookup

CVE-2026-124536 (GCVE-0-2026-124536)

Vulnerability from cvelistv5 – Published: 2026-11-14 11:51 – Updated: 2026-11-14 11:51

Title

JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse

Summary

JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse. The parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL. A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.

Severity

No CVSS data available.

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

CPANSec CNA under the redhat root

CNA scorecard C 61/100 over 359 records in the last 180 days details

References

1 reference

URL	Tags
https://metacpan.org/release/MLEHMANN/JSON-XS-4.0…	release-notes

Impacted products

1 product

Vendor	Product	Version	CPE status
		Affected: 0 , < 4.05 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "modules": [
            "JSON::XS"
          ],
          "packageName": "JSON-XS",
          "packageURL": "pkg:cpan/JSON-XS",
          "programFiles": [
            "XS.xs"
          ],
          "programRoutines": [
            {
              "name": "JSON::XS::incr_parse"
            }
          ],
          "repo": "https://cvs.schmorp.de/JSON-XS/",
          "versions": [
            {
              "lessThan": "4.05",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse.\n\nThe parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL.\n\nA peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770 Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-14T11:51:22.977Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://metacpan.org/release/MLEHMANN/JSON-XS-4.05/changes"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to JSON-XS 4.05 or later."
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "timeline": [
        {
          "lang": "en",
          "time": "2026-11-13T00:00:00.000Z",
          "value": "Version 4.05 released with fix."
        }
      ],
      "title": "JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse",
      "x_generator": {
        "engine": "cpansec-cna-tool 0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
    "assignerShortName": "CPANSec",
    "cveId": "CVE-2026-124536",
    "datePublished": "2026-11-14T11:51:22.977Z",
    "dateReserved": "2026-11-08T12:31:51.297Z",
    "dateUpdated": "2026-11-14T11:51:22.977Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://cpan.org/modules",
                "defaultStatus": "unaffected",
                "modules": [
                  "JSON::XS"
                ],
                "packageName": "JSON-XS",
                "packageURL": "pkg:cpan/JSON-XS",
                "programFiles": [
                  "XS.xs"
                ],
                "programRoutines": [
                  {
                    "name": "JSON::XS::incr_parse"
                  }
                ],
                "repo": "https://cvs.schmorp.de/JSON-XS/",
                "versions": [
                  {
                    "lessThan": "4.05",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse.\n\nThe parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL.\n\nA peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size."
          }
        ],
        "id": "CVE-2026-124536",
        "lastModified": "2026-11-14T12:17:42.840",
        "metrics": {},
        "published": "2026-11-14T12:17:42.840",
        "references": [
          {
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "url": "https://metacpan.org/release/MLEHMANN/JSON-XS-4.05/changes"
          }
        ],
        "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-770"
              }
            ],
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "type": "Secondary"
          }
        ]
      }
    }
  }
}

GHSA-JJ44-V2QC-WCV3

Vulnerability from github – Published: 2026-11-14 12:31 – Updated: 2026-11-14 12:31

Details

JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse.

The parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL.

A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-124536"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-11-14T12:17:42Z",
    "severity": null
  },
  "details": "JSON::XS versions before 4.05 for Perl allow memory exhaustion by buffering incremental input past max_size after a NUL byte in incr_parse.\n\nThe parser appends each chunk to its buffer and compares max_size with how far it has progressed, not with the buffer length. It treats a NUL byte as the end of the input, so a NUL within the first max_size bytes keeps it short of the limit. The buffer keeps growing, and incr_skip cannot remove the NUL.\n\nA peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.",
  "id": "GHSA-jj44-v2qc-wcv3",
  "modified": "2026-11-14T12:31:27Z",
  "published": "2026-11-14T12:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124536"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/MLEHMANN/JSON-XS-4.05/changes"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

Solutions

CNA · CPANSec

Upgrade to JSON-XS 4.05 or later.

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

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How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

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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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

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