Vulnerability-Lookup

ubuntu-cve-2022-4993

Vulnerability from osv_ubuntu

Published

2026-08-14 00:00

Modified

2026-08-14 00:00

Summary

Details

(HTML::FormHandler versions through 0.40068 for Perl allow attacker sel ...)

Severity

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2022-4993	REPORT
	https://www.cve.org/CVERecord?id=CVE-2022-4993	REPORT
	https://lists.security.metacpan.org/cve-announce/…	REPORT
	https://security.metacpan.org/patches/H/HTML-Form…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40064-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40064-1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40057-1",
        "0.40064-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40068-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40068-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40067-1",
        "0.40068-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40068-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40068-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40068-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40068-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40068-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40068-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40068-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40068-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40068-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libhtml-formhandler-perl",
            "binary_version": "0.40068-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libhtml-formhandler-perl",
        "purl": "pkg:deb/ubuntu/libhtml-formhandler-perl@0.40068-2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.40068-2"
      ]
    }
  ],
  "aliases": [],
  "details": "(HTML::FormHandler versions through 0.40068 for Perl allow attacker sel ...)",
  "id": "UBUNTU-CVE-2022-4993",
  "modified": "2026-08-14T00:00:00Z",
  "published": "2026-08-14T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2022-4993"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2022-4993"
    },
    {
      "type": "REPORT",
      "url": "https://lists.security.metacpan.org/cve-announce/msg/42659947/"
    },
    {
      "type": "REPORT",
      "url": "https://security.metacpan.org/patches/H/HTML-FormHandler/0.40068/CVE-2022-4993-r2.patch"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2022-4993"
  ]
}

CVE-2022-4993 (GCVE-0-2022-4993)

Vulnerability from cvelistv5 – Published: 2026-08-13 16:27 – Updated: 2026-08-15 12:13

Title

Summary

HTML::FormHandler versions through 0.40068 for Perl allow attacker selected method dispatch and resource exhaustion because _apply_actions and add_error use error message text built from request data as a Locale::Maketext bracket notation template. add_error hands its first argument to the language handle as the Locale::Maketext message key, and the default handle's lexicon sets `_AUTO`, so a string that is not a lexicon entry is compiled as a bracket notation template instead of being looked up. In a bracket group the first token names a method called on the language handle and the remaining tokens are its arguments. Three kinds of text the library did not author reach that position. _apply_actions installs a `$SIG{__WARN__}` handler that stores the warning text in `$error_message`, and a captured warning survives a successful action, so a field carrying a numeric transform turns `Argument "[sprintf,%50000000d,0]" isn't numeric` into the template; a warning quotes the submitted value verbatim, so the group is well formed and dispatches. `$error_message ||= $tobj->validate($new_value)` takes a type constraint's own failure message, which renders the rejected value through a partial dumper in bracket and comma form (Devel::PartialDump when Moose can load it, Type::Tiny's own dumper always), so a field with `apply => [ Str ]` given a parameter sent more than once, which arrives as an array, gets `Reference ["a","b"] did not pass type constraint "Str"` as its template, from a request that carries no bracket character of its own. A coercion or transform exception reaches it the same way. Beyond those, a validator whose message contains the field value puts that value in the template directly, and add_error replaces the message list with the contents of an arrayref first argument (`@message = @{$message[0]} if ref $message[0] eq 'ARRAY'`), so a value arriving as an array fills the argument slots from the same request as well. A malformed group such as `[0]` makes the compile croak, and HTML::FormHandler::I18N::maketext and add_error each re-raise that as a die, so process() throws. A well formed group naming sprintf reaches CORE::sprintf with an attacker chosen field width. Any caller that applies a type constraint or a transform to an untrusted field, or whose validator passes an untrusted field value to add_error, can be made to throw an unhandled exception out of process(), or to allocate an arbitrary amount of memory in one request, and an application whose language handle subclass defines side effecting public methods makes those callable with attacker chosen arguments. The dumped type constraint message is bounded to the exception, because both dumpers quote non-numeric elements so the method slot is never an attacker chosen name. The built-in messages pass fixed templates with the value in an argument slot, where it stays inert, and the built-in field types attach explicit message callbacks, so neither is affected.

Severity

9.1 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-14 11:14 UTC

CWE

CWE-1336 - Improper Neutralization of Special Elements Used in a Template Engine
CWE-470 - Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')

Assigner

CPANSec

References

6 references

URL	Tags
https://security.metacpan.org/patches/H/HTML-Form…	patch
https://github.com/gshank/html-formhandler/pull/159	issue-tracking
https://metacpan.org/release/GSHANK/HTML-FormHand…
https://metacpan.org/release/GSHANK/HTML-FormHand…
https://metacpan.org/release/GSHANK/HTML-FormHand…
https://www.cve.org/CVERecord?id=CVE-2012-6329	related

Impacted products

1 product

Vendor	Product	Version
		Affected: 0 , ≤ 0.40068 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 9.1,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2022-4993",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-14T11:14:18.115170Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-14T11:14:34.478Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "modules": [
            "HTML::FormHandler"
          ],
          "packageName": "HTML-FormHandler",
          "packageURL": "pkg:cpan/HTML-FormHandler",
          "programFiles": [
            "lib/HTML/FormHandler/Validate.pm",
            "lib/HTML/FormHandler/Field.pm",
            "lib/HTML/FormHandler/I18N.pm",
            "lib/HTML/FormHandler/I18N/en_us.pm"
          ],
          "programRoutines": [
            {
              "name": "HTML::FormHandler::Validate::_apply_actions"
            },
            {
              "name": "HTML::FormHandler::Field::add_error"
            },
            {
              "name": "HTML::FormHandler::Field::default_localize"
            },
            {
              "name": "HTML::FormHandler::I18N::maketext"
            }
          ],
          "repo": "https://github.com/gshank/html-formhandler",
          "versions": [
            {
              "lessThanOrEqual": "0.40068",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "HTML::FormHandler versions through 0.40068 for Perl allow attacker selected method dispatch and resource exhaustion because _apply_actions and add_error use error message text built from request data as a Locale::Maketext bracket notation template.\n\nadd_error hands its first argument to the language handle as the Locale::Maketext message key, and the default handle\u0027s lexicon sets `_AUTO`, so a string that is not a lexicon entry is compiled as a bracket notation template instead of being looked up. In a bracket group the first token names a method called on the language handle and the remaining tokens are its arguments.\n\nThree kinds of text the library did not author reach that position. _apply_actions installs a `$SIG{__WARN__}` handler that stores the warning text in `$error_message`, and a captured warning survives a successful action, so a field carrying a numeric transform turns `Argument \"[sprintf,%50000000d,0]\" isn\u0027t numeric` into the template; a warning quotes the submitted value verbatim, so the group is well formed and dispatches. `$error_message ||= $tobj-\u003evalidate($new_value)` takes a type constraint\u0027s own failure message, which renders the rejected value through a partial dumper in bracket and comma form (Devel::PartialDump when Moose can load it, Type::Tiny\u0027s own dumper always), so a field with `apply =\u003e [ Str ]` given a parameter sent more than once, which arrives as an array, gets `Reference [\"a\",\"b\"] did not pass type constraint \"Str\"` as its template, from a request that carries no bracket character of its own. A coercion or transform exception reaches it the same way. Beyond those, a validator whose message contains the field value puts that value in the template directly, and add_error replaces the message list with the contents of an arrayref first argument (`@message = @{$message[0]} if ref $message[0] eq \u0027ARRAY\u0027`), so a value arriving as an array fills the argument slots from the same request as well.\n\nA malformed group such as `[0]` makes the compile croak, and HTML::FormHandler::I18N::maketext and add_error each re-raise that as a die, so process() throws. A well formed group naming sprintf reaches CORE::sprintf with an attacker chosen field width. Any caller that applies a type constraint or a transform to an untrusted field, or whose validator passes an untrusted field value to add_error, can be made to throw an unhandled exception out of process(), or to allocate an arbitrary amount of memory in one request, and an application whose language handle subclass defines side effecting public methods makes those callable with attacker chosen arguments. The dumped type constraint message is bounded to the exception, because both dumpers quote non-numeric elements so the method slot is never an attacker chosen name. The built-in messages pass fixed templates with the value in an argument slot, where it stays inert, and the built-in field types attach explicit message callbacks, so neither is affected."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-1336",
              "description": "CWE-1336 Improper Neutralization of Special Elements Used in a Template Engine",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-470",
              "description": "CWE-470 Use of Externally-Controlled Input to Select Classes or Code (\u0027Unsafe Reflection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-15T12:13:44.455Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://security.metacpan.org/patches/H/HTML-FormHandler/0.40068/CVE-2022-4993-r2.patch"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/gshank/html-formhandler/pull/159"
        },
        {
          "url": "https://metacpan.org/release/GSHANK/HTML-FormHandler-0.40068/source/lib/HTML/FormHandler/Validate.pm#L161-261"
        },
        {
          "url": "https://metacpan.org/release/GSHANK/HTML-FormHandler-0.40068/source/lib/HTML/FormHandler/Field.pm#L861-876"
        },
        {
          "url": "https://metacpan.org/release/GSHANK/HTML-FormHandler-0.40068/source/lib/HTML/FormHandler/I18N/en_us.pm#L9-11"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://www.cve.org/CVERecord?id=CVE-2012-6329"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "timeline": [
        {
          "lang": "en",
          "time": "2022-01-10T00:00:00.000Z",
          "value": "Issue was first reported to author without a proof of concept."
        },
        {
          "lang": "en",
          "time": "2024-10-27T00:00:00.000Z",
          "value": "Issue was forwarded to CPANSec."
        },
        {
          "lang": "en",
          "time": "2026-06-22T00:00:00.000Z",
          "value": "Investigation and development of proof of concept by CPANSec, aided by LLM tooling."
        },
        {
          "lang": "en",
          "time": "2026-07-02T00:00:00.000Z",
          "value": "Issue was again reported to author with proof of concept."
        },
        {
          "lang": "en",
          "time": "2026-07-30T00:00:00.000Z",
          "value": "Additional analysis and development of patch by CPANSec, aided by LLM tooling."
        },
        {
          "lang": "en",
          "time": "2026-08-13T00:00:00.000Z",
          "value": "CVE-2022-4993 published"
        }
      ],
      "title": "HTML::FormHandler versions through 0.40068 for Perl allow attacker selected method dispatch and resource exhaustion because _apply_actions and add_error use error message text built from request data as a Locale::Maketext bracket notation template",
      "workarounds": [
        {
          "lang": "en",
          "value": "No fixed release is available. Apply the patch, which escapes the bracket notation metacharacters in the trapped warning, the type constraint message and the coercion or transform exception before they are used as a template, and in element 0 of an arrayref first argument. A message an application builds from a field value cannot be told apart from a template inside the library: pass a fixed template to add_error and supply the value as an argument, as the built-in messages do (`$field-\u003eadd_error(\u0027[_1] not allowed\u0027, $field-\u003evalue)`), so the value lands in an inert argument slot. Setting an allowlist on the language handle bounds the methods bracket notation can reach."
        }
      ],
      "x_generator": {
        "engine": "cpansec-cna-tool 0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
    "assignerShortName": "CPANSec",
    "cveId": "CVE-2022-4993",
    "datePublished": "2026-08-13T16:27:47.498Z",
    "dateReserved": "2026-06-23T17:33:58.500Z",
    "dateUpdated": "2026-08-15T12:13:44.455Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

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.

Action not permitted

ubuntu-cve-2022-4993

Vulnerability from osv_ubuntu

CVE-2022-4993 (GCVE-0-2022-4993)

Tags

Sightings

Nomenclature