CVE-2026-8878Network attack vector

Sensitive filtering data disclosure via public endpoints

Published Jun 3, 2026 · Updated Jun 3, 2026

Inadequate encryption in Securly Chrome Extension 3.0.7 and earlier allows remote attackers to read sensitive filtering data via public endpoints. Public endpoints return internal keyword lists, blocklists, and rule definitions as SHA-1 hashes protected only by a reversible Caesar cipher. No authentication or user interaction is required; reversing the obfuscation reveals the hash values and filtering logic, without reported integrity or availability impact.

CVSS severity7.5
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Inadequate encryption in Securly Chrome Extension 3.0.7 and earlier allows remote attackers to read sensitive filtering data via public endpoints. Public endpoints return internal keyword lists, blocklists, and rule definitions as SHA-1 hashes protected only by a reversible Caesar cipher. No authentication or user interaction is required; reversing the obfuscation reveals the hash values and filtering logic, without reported integrity or availability impact.

The record

CVE
CVE-2026-8878
Published
Jun 3, 2026
Updated
Jun 3, 2026
Vendor
Securly
Product
Securly Chrome Extension
Classifications
CWE-326
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 3, 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=0 <=3.0.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Securly · Securly Chrome Extensionversion=0 <=3.0.7

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-326Inadequate Encryption Strength

Public exploit references

No public exploit references are available in this record.

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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