How severe is CVE-2021-36767?

CVE-2021-36767 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-36767 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36767?

CVE-2021-36767 primarily affects Digi Realport. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36767?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-36767 published?

CVE-2021-36767 was published on 2021-10-08 and last updated on 2026-06-17.

CVE-2021-36767

CVE-2021-36767 is a critical-severity vulnerability in Digi Realport with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-916.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-916
Affected product: Digi Realport
Published: 2021-10-08
Last modified: 2026-06-17

Description

In Digi RealPort through 4.10.490, authentication relies on a challenge-response mechanism that gives access to the server password, making the protection ineffective. An attacker may send an unauthenticated request to the server. The server will reply with a weakly-hashed version of the server's access password. The attacker may then crack this hash offline in order to successfully login to the server.

Frequently asked questions

What is CVE-2021-36767?: In Digi RealPort through 4.10.490, authentication relies on a challenge-response mechanism that gives access to the server password, making the protection ineffective. An attacker may send an unauthenticated request to the server. The server will reply with a weakly-hashed version of the server's access password. The attacker may then crack this hash offline in order to successfully login to the server.
How severe is CVE-2021-36767?: CVE-2021-36767 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-36767 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36767?: CVE-2021-36767 primarily affects Digi Realport. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36767?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-36767 published?: CVE-2021-36767 was published on 2021-10-08 and last updated on 2026-06-17.

References

https://raw.githubusercontent.com/reidmefirst/vuln-disclosure/main/2021-02.txt

Affected products (20)

cpe:2.3:a:digi:realport:*:*:*:*:*:linux:*:*
cpe:2.3:a:digi:realport:*:*:*:*:*:windows:*:*
cpe:2.3:o:digi:connectport_ts_8\/16_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:connectport_lts_8\/16\/32_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:passport_integrated_console_server_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:cm_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:portserver_ts_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:portserver_ts_mei_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:portserver_ts_mei_hardened_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:portserver_ts_m_mei_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:6350-sr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:portserver_ts_p_mei_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:transport_wr11_xt_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:one_ia_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:wr31_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:wr44_r_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:connect_es_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:wr21_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:one_iap_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:digi:one_iap_haz_firmware:*:*:*:*:*:*:*:*

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