Vulnerability-Lookup

GHSA-W4CM-GVHJ-CGW6

Vulnerability from github – Published: 2026-09-23 21:23 – Updated: 2026-09-23 21:23

Summary

Jawn: Quadratic parsing effort in AsyncParser

Details

AsyncParser can be forced to perform O(n^2) work on the length of the input. When a single JSON token arrives across many small chunks, each absorb call rescans the incomplete token from the start.

Impact

Denial of service via CPU exhaustion when parsing untrusted JSON.

Preconditions: - Application uses AsyncParser - Attacker can send large tokens with control over chunk sizes.

Patches

Fixed in jawn-parser-1.7.0.

Workarounds

If you can't upgrade immediately: - Use the synchronous Parser. - Buffer incoming bytes into larger chunks before calling absorb

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": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.6.0"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.typelevel:jawn-parser_2.12"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.6.0"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.typelevel:jawn-parser_2.13"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.6.0"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.typelevel:jawn-parser_3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-61814"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-407"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-23T21:23:58Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "`AsyncParser` can be forced to perform O(n^2) work on the length of the input.  When a single JSON token arrives across many small chunks, each `absorb` call rescans the incomplete token from the start.\n\n### Impact\n\nDenial of service via CPU exhaustion when parsing untrusted JSON.\n\nPreconditions:\n- Application uses `AsyncParser`\n- Attacker can send large tokens with control over chunk sizes.\n\n### Patches\n\nFixed in jawn-parser-1.7.0.\n\n### Workarounds\n\nIf you can\u0027t upgrade immediately:\n- Use the synchronous `Parser`.\n- Buffer incoming bytes into larger chunks before calling `absorb`",
  "id": "GHSA-w4cm-gvhj-cgw6",
  "modified": "2026-09-23T21:23:59Z",
  "published": "2026-09-23T21:23:58Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/typelevel/jawn/security/advisories/GHSA-w4cm-gvhj-cgw6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/typelevel/jawn/commit/cddcd5e3387c356b05953f7b2af103d309687e4b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/typelevel/jawn"
    },
    {
      "type": "WEB",
      "url": "https://github.com/typelevel/jawn/releases/tag/v1.7.0"
    }
  ],
  "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"
    }
  ],
  "summary": "Jawn: Quadratic parsing effort in AsyncParser"
}

CVE-2026-61814 (GCVE-0-2026-61814)

Vulnerability from cvelistv5 – Published: 2026-09-23 18:39 – Updated: 2026-09-23 19:41

Title

Jawn: Quadratic parsing effort in AsyncParser

Summary

Jawn is an open source JSON parser. Prior to 1.7.0, Jawn's AsyncParser can perform quadratic work when a single JSON token is delivered across many small chunks because each absorb call rescans the incomplete token from the start. A remote attacker who controls untrusted JSON input and its chunk sizes can exhaust CPU resources and cause denial of service in applications using AsyncParser. This issue is fixed in version 1.7.0.

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 2026-09-23 19:25 UTC

CWE

CWE-400 - Uncontrolled Resource Consumption
CWE-407 - Inefficient Algorithmic Complexity

Assigner

GitHub_M mitre root Scorecard

References

3 references

URL	Tags
https://github.com/typelevel/jawn/security/adviso…	x_refsource_CONFIRM
https://github.com/typelevel/jawn/commit/cddcd5e3…	x_refsource_MISC
https://github.com/typelevel/jawn/releases/tag/v1.7.0	x_refsource_MISC

Impacted products

4 products

Vendor	Product	Version
typelevel	jawn	Affected: < 1.7.0
org.typelevel	jawn-parser_2.12	Affected: < 1.7.0
org.typelevel	jawn-parser_2.13	Affected: < 1.7.0
org.typelevel	jawn-parser_3	Affected: < 1.7.0

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-61814",
                "options": [
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                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-23T19:25:56.569425Z",
                "version": "2.0.3"
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          "versions": [
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          "versions": [
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        }
      ],
      "metrics": [
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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.

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.
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