How severe is CVE-2021-25846?

CVE-2021-25846 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-25846 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25846?

CVE-2021-25846 primarily affects Moxa Vport 06ec-2v26m Firmware. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-25846?

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-2021-25846 published?

CVE-2021-25846 was published on 2021-05-10 and last updated on 2026-06-17.

CVE-2021-25846

CVE-2021-25846 is a high-severity vulnerability in Moxa Vport 06ec-2v26m Firmware with a CVSS 3.x base score of 7.5. 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-191.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Moxa Vport 06ec-2v26m Firmware
Published: 2021-05-10
Last modified: 2026-06-17

Description

Improper validation of the ChassisID TLV in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series, version 1.1, allows attackers to cause a denial of service due to a negative number passed to the memcpy function via a crafted lldp packet.

Frequently asked questions

What is CVE-2021-25846?: Improper validation of the ChassisID TLV in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series, version 1.1, allows attackers to cause a denial of service due to a negative number passed to the memcpy function via a crafted lldp packet.
How severe is CVE-2021-25846?: CVE-2021-25846 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-25846 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25846?: CVE-2021-25846 primarily affects Moxa Vport 06ec-2v26m Firmware. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-25846?: 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-2021-25846 published?: CVE-2021-25846 was published on 2021-05-10 and last updated on 2026-06-17.

References

Affected products (16)

cpe:2.3:o:moxa:vport_06ec-2v26m_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v36m-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v36m-ct_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v36m-ct-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v42m_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v42m-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v42m-ct_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v42m-ct-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v60m_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v60m-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v60m-ct_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v60m-ct-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v80m_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v80m-t_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v80m-ct_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:vport_06ec-2v80m-ct-t_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Moxa Vport 06ec-2v26m Firmware

CVE-2021-25848 — Critical (CVSS 9.1): Improper validation of the length field of LLDP-MED TLV in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series,…
CVE-2021-25847 — Critical (CVSS 9.1): Improper validation of the length field of LLDP-MED TLV in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series,…
CVE-2021-25849 — High (CVSS 7.5): An integer underflow was discovered in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series, version 1.1, improper…
CVE-2021-25845 — High (CVSS 7.5): Improper validation of the ChassisID TLV in userdisk/vport_lldpd in Moxa Camera VPort 06EC-2V Series, version 1.1,…

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