HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-19873
StatePUBLISHED
AssignerCPANSec
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-31 10:16:49 UTC
Updated2026-08-31 18:17:14 UTC
DescriptionHTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements. When a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. Nothing caps the value, and no attribute lets an application impose a limit. The count is read on every request, before the form decides whether it was submitted, so a plain GET reaches the clone loop with no credentials, no session and no request body. Nesting multiplies: a Repeatable inside a Repeatable takes a counter at each level, so an outer and an inner value of 100 build 10,000 clones. Once the form is submitted, each cloned field's constraints scan the whole element tree in _find_field_value, so cost grows faster than linearly with the count. A single request exhausts memory and CPU. The latest release on CPAN is 2.07, from 2018. Version 2.08 exists only in the git repository.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from ADP

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

Problem Types: CWE-770 | CWE-1284 | CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input | CWE-770 CWE-770 Allocation of Resources Without Limits or Throttling

VersionSourceTypeScoreSeverityVector
3.1ADPDECLARED7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
3.1134c704f-9b21-4f2e-91b3-4a467353bcc0Secondary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

References

ReferenceSourceLinkTags
security.metacpan.org/patches/H/HTML-FormFu/2.08/CVE-2026-19873-r1.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e security.metacpan.org
www.openwall.com/lists/oss-security/2026/08/31/7 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com
github.com/FormFu/HTML-FormFu/issues/71 9b29abf9-4ab0-4765-b253-1875cd9b441e github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Additional Advisory Data

Solutions

CNA: Apply the patch. There is no fixed release.

Workarounds

CNA: For deployments that cannot apply the patch, reject or clamp the counter parameter before passing the query to process. Where the client-side repeat feature is not needed, unsetting counter_name stops the count being read from the query string.

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report