How severe is CVE-2023-27989?

CVE-2023-27989 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-27989 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27989?

CVE-2023-27989 primarily affects Zyxel Lte7480-m804 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27989?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-27989 published?

CVE-2023-27989 was published on 2023-06-05 and last updated on 2026-06-17.

CVE-2023-27989

CVE-2023-27989 is a medium-severity vulnerability in Zyxel Lte7480-m804 Firmware with a CVSS 3.x base score of 6.5. 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-120.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Zyxel Lte7480-m804 Firmware
Published: 2023-06-05
Last modified: 2026-06-17

Description

A buffer overflow vulnerability in the CGI program of the Zyxel NR7101 firmware versions prior to V1.00(ABUV.8)C0 could allow a remote authenticated attacker to cause denial of service (DoS) conditions by sending a crafted HTTP request to a vulnerable device.

Frequently asked questions

What is CVE-2023-27989?: A buffer overflow vulnerability in the CGI program of the Zyxel NR7101 firmware versions prior to V1.00(ABUV.8)C0 could allow a remote authenticated attacker to cause denial of service (DoS) conditions by sending a crafted HTTP request to a vulnerable device.
How severe is CVE-2023-27989?: CVE-2023-27989 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-27989 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27989?: CVE-2023-27989 primarily affects Zyxel Lte7480-m804 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27989?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-27989 published?: CVE-2023-27989 was published on 2023-06-05 and last updated on 2026-06-17.

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-buffer-overflow-vulnerability-in-4g-lte-and-5g-nr-outdoor-routers

Affected products (4)

cpe:2.3:o:zyxel:lte7480-m804_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7490-m904_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:nr7101_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:nebula_nr7101_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Zyxel Lte7480-m804 Firmware

CVE-2022-43389 — High (CVSS 8.6): A buffer overflow vulnerability in the library of the web server in Zyxel NR7101 firmware prior to V1.15(ACCC.3)C0,…
CVE-2024-8748 — High (CVSS 7.5): A buffer overflow vulnerability in the packet parser of the third-party library "libclinkc" in Zyxel VMG8825-T50K…
CVE-2022-43392 — Medium (CVSS 6.5): A buffer overflow vulnerability in the parameter of web server in Zyxel NR7101 firmware prior to V1.15(ACCC.3)C0, which…
CVE-2022-43391 — Medium (CVSS 6.5): A buffer overflow vulnerability in the parameter of the CGI program in Zyxel NR7101 firmware prior to V1.15(ACCC.3)C0,…
CVE-2021-35036 — Medium (CVSS 6.5): A cleartext storage of information vulnerability in the Zyxel VMG3625-T50B firmware version V5.50(ABTL.0)b2k could…
CVE-2024-0816 — Medium (CVSS 5.5): The buffer overflow vulnerability in the DX3300-T1 firmware version V5.50(ABVY.4)C0 could allow an authenticated local…

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