CVE-2020-36946Public exploitNetwork attack vector

Unauthenticated service crash via oversized login Referer

Published Jan 27, 2026 · Updated Jan 27, 2026

Resource exhaustion in the login endpoint in Flexense Ltd. SyncBreeze 10.0.28 allows remote attackers to crash the service. The HTTP handler accepts a POST /login request whose Referer header appends 1,000 bytes to the /login path without enforcing a resource limit. No authentication or user interaction is required; the published proof of concept reaches the web service over TCP port 80 and interrupts availability.

CVSS severity8.7
High
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in the login endpoint in Flexense Ltd. SyncBreeze 10.0.28 allows remote attackers to crash the service. The HTTP handler accepts a POST /login request whose Referer header appends 1,000 bytes to the /login path without enforcing a resource limit. No authentication or user interaction is required; the published proof of concept reaches the web service over TCP port 80 and interrupts availability.

The record

CVE
CVE-2020-36946
Published
Jan 27, 2026
Updated
Jan 27, 2026
Vendor
Flexense Ltd.
Product
SyncBreeze
Classifications
CWE-770, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.28

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Flexense Ltd. · SyncBreezeversion=10.0.28

Published CVSS scores

8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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