CVE-2020-5539Network attack vector

User impersonation via victim session ID reuse

Published Mar 2, 2020 · Updated Aug 4, 2024

Session management failure in GRANDIT 1.6, 2.0, 2.1, 2.2, 2.3, and 3.0 allows remote attackers to impersonate users and read or alter data. The application fails to prevent reuse of a victim's login-associated session ID, allowing that identifier to authorize later screen requests. Exploitation requires victim interaction and possession of the victim's session ID, and access is bounded by the impersonated account.

CVSS severity4.2
Medium
EPSS probability0.84%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Session management failure in GRANDIT 1.6, 2.0, 2.1, 2.2, 2.3, and 3.0 allows remote attackers to impersonate users and read or alter data. The application fails to prevent reuse of a victim's login-associated session ID, allowing that identifier to authorize later screen requests. Exploitation requires victim interaction and possession of the victim's session ID, and access is bounded by the impersonated account.

The record

CVE
CVE-2020-5539
Published
Mar 2, 2020
Updated
Aug 4, 2024
Vendor
GRANDIT Corporation
Product
GRANDIT
Classifications
CWE-639, T1550.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 2, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=Ver.1.6, Ver.2.0, Ver.2.1, Ver.2.2, Ver.2.3, and Ver.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GRANDIT Corporation · GRANDITversion=Ver.1.6, Ver.2.0, Ver.2.1, Ver.2.2, Ver.2.3, and Ver.3.0

Published CVSS scores

6.4NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:N
4.0JPCERT/CCAV:N/AC:H/Au:N/C:P/I:P/A:N
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
4.2JPCERT/CCCVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1550.004Use Alternate Authentication Material: Web Session Cookie

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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