CVE-2023-4698Public exploitNetwork attack vector

Unauthenticated data access via unchecked JWT validity

Published Sep 1, 2023 · Updated Sep 30, 2024

Improper input validation in Memos before 0.13.2 allows remote attackers to access protected note data via crafted access tokens. The JWTMiddleware function in server/jwt.go checked token claims but omitted the accessToken.Valid test, allowing invalid tokens to reach authenticated handlers. Exploitation requires a network-reachable Memos instance and results in confidentiality loss without demonstrated data modification or service interruption.

CVSS severity7.5
High
EPSS probability0.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Memos before 0.13.2 allows remote attackers to access protected note data via crafted access tokens. The JWTMiddleware function in server/jwt.go checked token claims but omitted the accessToken.Valid test, allowing invalid tokens to reach authenticated handlers. Exploitation requires a network-reachable Memos instance and results in confidentiality loss without demonstrated data modification or service interruption.

The record

CVE
CVE-2023-4698
Published
Sep 1, 2023
Updated
Sep 30, 2024
Vendor
Memos
Product
Memos
Classifications
CWE-20, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 1, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 30, 2024Record 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=unspecified <0.13.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Memos · Memosversion=unspecified <0.13.2

Published CVSS scores

7.5[email protected]CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
7.5[email protected]CVSS:3.0/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-20Improper Input Validation
T1190Exploit Public-Facing Application

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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