VulnerabilityPublished 3 Nov 2026

CVE-2026-120650: CGI (Perl module) · Unthrottled Resource Allocation

Affects CGI (Perl module)Source CVE Database V5

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Not known to be exploited : upgrade to 5.00 soon.

Data as of 4 Nov 2026, 00:59 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Patch: Available – fixed in 5.00

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade CGI (Perl module) to 5.00.

Affected software

Product	Affected	Fixed in
CGI	Affected <5.00	Fixed in 5.00
CPANCGI`pkg:cpan/CGI`Other threats	Affected <5.00	Fixed in 5.00

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Upgrade to CGI version 5.00 or later, where this vulnerability is fixed. Until then, consider implementing external request size and parameter limits at the web server or application firewall level to mitigate resource exhaustion risks.

Description

CGI versions prior to 5.00 for Perl have a vulnerability that allows resource exhaustion due to lack of limits on request size, parameters, and uploads. The default setting for $CGI::POST_MAX imposes no limit, and certain multipart body types bypass enforcement. This can lead to memory, CPU, and disk exhaustion.

Impact

An attacker can exploit this vulnerability to cause denial of service by exhausting server memory, CPU, or disk resources through specially crafted HTTP requests with large or numerous parameters and uploads. This can degrade or disrupt the availability of the affected CGI service.

Summary

CVE-2026-120650 describes a resource exhaustion vulnerability in CGI versions before 5.00 for Perl. The flaw arises because the module does not enforce limits on request size, number of parameters, or uploaded data size. Specifically, $CGI::POST_MAX defaults to unlimited, and even when set, it is not enforced for chunked multipart bodies or multipart bodies missing a boundary parameter. Uploaded bodies saved as PUTDATA, POSTDATA, or PATCHDATA are read entirely into memory without limits on the number of parameters or uploads, enabling potential exhaustion of memory, CPU, and disk resources.

CWE-770Allocation of Resources Without Limits or Throttling (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #25
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Requirements
Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
Architecture and Design
Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
Architecture and Design
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V8.1.4 (opens in a new tab)
V13.4.1 (opens in a new tab)
V11.1.4 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Exponential Data Expansion (opens in a new tab)
Serialized Data Parameter Blowup (opens in a new tab)
Serialized Data with Nested Payloads (opens in a new tab)
Oversized Serialized Data Payloads (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Nov 2026, 00:59 UTC

WeaknessesCWE-770

Technical details

References

Community reviews

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