How severe is CVE-2021-43430?

CVE-2021-43430 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43430 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43430?

CVE-2021-43430 affects Bigantsoft Bigant Office Messenger 5. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43430?

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

When was CVE-2021-43430 published?

CVE-2021-43430 was published on 2022-04-07 and last updated on 2026-06-17.

CVE-2021-43430

CVE-2021-43430 is a high-severity vulnerability in Bigantsoft Bigant Office Messenger 5 with a CVSS 3.x base score of 8.8. 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-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Bigantsoft Bigant Office Messenger 5
Published: 2022-04-07
Last modified: 2026-06-17

Description

An Access Control vulnerability exists in BigAntSoft BigAnt office messenger 5.6 via im_webserver, which could let a malicious user upload PHP Trojan files.

Frequently asked questions

What is CVE-2021-43430?: An Access Control vulnerability exists in BigAntSoft BigAnt office messenger 5.6 via im_webserver, which could let a malicious user upload PHP Trojan files.
How severe is CVE-2021-43430?: CVE-2021-43430 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43430 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43430?: CVE-2021-43430 affects Bigantsoft Bigant Office Messenger 5. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43430?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-43430 published?: CVE-2021-43430 was published on 2022-04-07 and last updated on 2026-06-17.

References

https://github.com/Flash1201/bug/blob/main/bigant

Affected products (1)

cpe:2.3:a:bigantsoft:bigant_office_messenger_5:5.6:*:*:*:*:*:*:*

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