CVE-2023-28356

highpriority · track · 30EPSS 0.007 · 54 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.72% (54th) EPSS

CVSS 7.5 · high

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

A vulnerability has been identified where a maliciously crafted message containing a specific chain of characters can cause the chat to enter a hot loop on one of the processes, consuming ~120% CPU and rendering the service unresponsive.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-770US

affected products (2)

Products and version ranges known to be affected.

n/a Rocket.Chat≤ This issue has been fixed in version 6.0> and is backported for the supported versions. Check this document for more info: https://docs.rocket.chat/resources/get-support/enterprise-support#rocket.chat-versionsenisa_euvdEU
rocket.chat rocket.chat< 6.0.0nvdUScpe:2.3:a:rocket.chat:rocket.chat:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2023-05-11modified 2026-06-17

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references (5)

External citations — patches, advisories, analysis.

scry

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