CVE-2026-41146 (GCVE-0-2026-41146)

Vulnerability from cvelistv5 – Published: 2026-04-22 01:07 – Updated: 2026-04-22 13:09
VLAI
Title
facil.io and downstream iodine ruby gem vulnerable to uncontrolled resource consumption and loop with unreachable exit condition
Summary
facil.io is a C micro-framework for web applications. Prior to commit 5128747363055201d3ecf0e29bf0a961703c9fa0, `fio_json_parse` can enter an infinite loop when it encounters a nested JSON value starting with `i` or `I`. The process spins in user space and pegs one CPU core at ~100% instead of returning a parse error. Because `iodine` vendors the same parser code, the issue also affects `iodine` when it parses attacker-controlled JSON. The smallest reproducer I found is `[i`. The quoted-value form that originally exposed the issue, `[""i`, reaches the same bug because the parser tolerates missing commas and then treats the trailing `i` as the start of another value. Commit 5128747363055201d3ecf0e29bf0a961703c9fa0 fixes the issue.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-22 13:09 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
boazsegev facil.io Affected: < 5128747363055201d3ecf0e29bf0a961703c9fa0
Create a notification for this product.
boazsegev iodine Affected: < 0.7.59
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-41146",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-22T13:09:34.301684Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-22T13:09:38.075Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "facil.io",
          "vendor": "boazsegev",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5128747363055201d3ecf0e29bf0a961703c9fa0"
            }
          ]
        },
        {
          "product": "iodine",
          "vendor": "boazsegev",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.7.59"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "facil.io is a C micro-framework for web applications. Prior to commit 5128747363055201d3ecf0e29bf0a961703c9fa0, `fio_json_parse` can enter an infinite loop when it encounters a nested JSON value starting with `i` or `I`. The process spins in user space and pegs one CPU core at ~100% instead of returning a parse error. Because `iodine` vendors the same parser code, the issue also affects `iodine` when it parses attacker-controlled JSON. The smallest reproducer I found is `[i`. The quoted-value form that originally exposed the issue, `[\"\"i`, reaches the same bug because the parser tolerates missing commas and then treats the trailing `i` as the start of another value. Commit 5128747363055201d3ecf0e29bf0a961703c9fa0 fixes the issue."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-400",
              "description": "CWE-400: Uncontrolled Resource Consumption",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-835",
              "description": "CWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-22T01:07:28.660Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm"
        },
        {
          "name": "https://github.com/boazsegev/facil.io/commit/5128747363055201d3ecf0e29bf0a961703c9fa0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/boazsegev/facil.io/commit/5128747363055201d3ecf0e29bf0a961703c9fa0"
        }
      ],
      "source": {
        "advisory": "GHSA-2x79-gwq3-vxxm",
        "discovery": "UNKNOWN"
      },
      "title": "facil.io and downstream iodine ruby gem vulnerable to uncontrolled resource consumption and loop with unreachable exit condition"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-41146",
    "datePublished": "2026-04-22T01:07:28.660Z",
    "dateReserved": "2026-04-17T12:59:15.739Z",
    "dateUpdated": "2026-04-22T13:09:38.075Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-41146",
                    "options": [
                      {
                        "Exploitation": "poc"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-04-22T13:09:34.301684Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-04-22T13:09:26.346Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "references": [
              {
                "tags": [
                  "exploit"
                ],
                "url": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm"
              }
            ],
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "product": "facil.io",
              "vendor": "boazsegev",
              "versions": [
                {
                  "status": "affected",
                  "version": "\u003c 5128747363055201d3ecf0e29bf0a961703c9fa0"
                }
              ]
            },
            {
              "product": "iodine",
              "vendor": "boazsegev",
              "versions": [
                {
                  "status": "affected",
                  "version": "\u003c 0.7.59"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "facil.io is a C micro-framework for web applications. Prior to commit 5128747363055201d3ecf0e29bf0a961703c9fa0, `fio_json_parse` can enter an infinite loop when it encounters a nested JSON value starting with `i` or `I`. The process spins in user space and pegs one CPU core at ~100% instead of returning a parse error. Because `iodine` vendors the same parser code, the issue also affects `iodine` when it parses attacker-controlled JSON. The smallest reproducer I found is `[i`. The quoted-value form that originally exposed the issue, `[\"\"i`, reaches the same bug because the parser tolerates missing commas and then treats the trailing `i` as the start of another value. Commit 5128747363055201d3ecf0e29bf0a961703c9fa0 fixes the issue."
            }
          ],
          "metrics": [
            {
              "cvssV4_0": {
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "NETWORK",
                "baseScore": 8.7,
                "baseSeverity": "HIGH",
                "privilegesRequired": "NONE",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
                "version": "4.0",
                "vulnAvailabilityImpact": "HIGH",
                "vulnConfidentialityImpact": "NONE",
                "vulnIntegrityImpact": "NONE"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-400",
                  "description": "CWE-400: Uncontrolled Resource Consumption",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            },
            {
              "descriptions": [
                {
                  "cweId": "CWE-835",
                  "description": "CWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-04-22T01:07:28.660Z",
            "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
            "shortName": "GitHub_M"
          },
          "references": [
            {
              "name": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm",
              "tags": [
                "x_refsource_CONFIRM"
              ],
              "url": "https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm"
            },
            {
              "name": "https://github.com/boazsegev/facil.io/commit/5128747363055201d3ecf0e29bf0a961703c9fa0",
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "https://github.com/boazsegev/facil.io/commit/5128747363055201d3ecf0e29bf0a961703c9fa0"
            }
          ],
          "source": {
            "advisory": "GHSA-2x79-gwq3-vxxm",
            "discovery": "UNKNOWN"
          },
          "title": "facil.io and downstream iodine ruby gem vulnerable to uncontrolled resource consumption and loop with unreachable exit condition"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "assignerShortName": "GitHub_M",
        "cveId": "CVE-2026-41146",
        "datePublished": "2026-04-22T01:07:28.660Z",
        "dateReserved": "2026-04-17T12:59:15.739Z",
        "dateUpdated": "2026-04-22T13:09:38.075Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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

JSON

Loading timeline…




    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.