CVE-2021-20597
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU...
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series Safety CPU modules R08/16/32/120SFCPU firmware versions "26" and prior and Mitsubishi Electric MELSEC iQ-R series SIL2 Process CPU modules R08/16/32/120PSFCPU firmware versions "11" and prior allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series Safety CPU modules R08/16/32/120SFCPU firmware versions "26" and prior and Mitsubishi Electric MELSEC iQ-R series SIL2 Process CPU modules R08/16/32/120PSFCPU firmware versions "11" and prior allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.
- Record
CVE-2021-20597- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 2.0
- 6.4 Medium
AV:N/AC:L/Au:N/C:P/I:P/A:N - Weakness
- CWE-522
- Updated
- 2026-11-02
CVE List No score
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series Safety CPU modules R08/16/32/120SFCPU firmware versions "26" and prior and Mitsubishi Electric MELSEC iQ-R series SIL2 Process CPU modules R08/16/32/120PSFCPU firmware versions "11" and prior allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.
- Record
CVE-2021-20597- Updated
- 2026-11-02
EUVDEUVD-2021-8015 No score
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series Safety CPU modules R08/16/32/120SFCPU firmware versions "26" and prior and Mitsubishi Electric MELSEC iQ-R series SIL2 Process CPU modules R08/16/32/120PSFCPU firmware versions "11" and prior allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.
- Record
EUVD-2021-8015- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-46vr-p4g8-f826
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU...
Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU modules (R08/16/32/120SFCPU all versions, R08/16/32/120PSFCPU all versions) allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.
- Record
GHSA-46vr-p4g8-f826- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-522
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20597 is a critical vulnerability (CVSS 9.1) in Mitsubishielectric R08psfcpu Firmware, published August 6, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.22%, the 82nd percentile. No source names a fixed version.