VulnerabilityPublished 13 Aug 2026Updated 27 Oct 2026

CVE-2025-68480: Esphome · Marshmallow has DoS in Schema.load(many)

Affects esphomeSource GCVE Database

Authoritative record:CVE-2025-68480· Medium 5.3

Not known to be exploited · CVSS 5.3 Medium : upgrade to 2025.12.1_1 or 2023.10.0 when convenient.

Data as of 27 Oct 2026, 21:01 UTC

CVSS 3.1 base score

5.3Medium

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 2025.12.1_1, 2023.10.0

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

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

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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 esphome to 2025.12.1_1 or 2023.10.0.

Affected software

Product	Affected	Fixed in
Homebrewesphome`pkg:brew/esphome`Other threats	Affected >=2022.1.2 <2023.10.0 >=2024.2.1 <2025.12.1_1	Fixed in 2023.10.0 2025.12.1_1

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

AI-suggested

Apply the official patches available in Esphome versions 2023.10.0 and 2025.12.1_1 to remediate this vulnerability. Alternatively, implement the provided workaround to validate input type and fail fast before processing, which mitigates excessive CPU consumption.

Description

CVE-2025-68480 is a denial of service vulnerability in Esphome's Marshmallow library affecting the Schema.load function when called with many=True. A moderately sized input can cause excessive CPU consumption, leading to service disruption. Fixed versions 2023.10.0 and 2025.12.1_1 address this issue. A workaround involves validating input type before processing to fail fast.

Impact

An attacker can cause a denial of service by sending crafted input to the Schema.load method with many=True, resulting in high CPU usage and potential service unavailability. There is no impact on confidentiality or integrity.

Summary

The vulnerability in Esphome's Marshmallow library occurs in the Schema.load(data, many=True) method, which is susceptible to denial of service attacks due to disproportionate CPU usage triggered by moderately sized requests. This flaw can degrade service availability by exhausting processing resources. Official patches are available in versions 2023.10.0 and 2025.12.1_1. A recommended workaround is to validate that the input data is a list before loading each item individually, thereby preventing excessive CPU consumption.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Oct 2026, 21:01 UTC

Technical details

References

Community reviews

Related threats