How severe is CVE-2023-26793?

CVE-2023-26793 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-2023-26793 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26793?

CVE-2023-26793 affects Libmodbus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-26793?

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.

Does CVE-2023-26793 have an EU (EUVD) identifier?

Yes. CVE-2023-26793 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-30586.

When was CVE-2023-26793 published?

CVE-2023-26793 was published on 2024-05-01 and last updated on 2026-06-17.

CVE-2023-26793

CVE-2023-26793 is a critical-severity vulnerability in Libmodbus 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-122.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-30586
Weakness: CWE-122
Affected product: Libmodbus
Published: 2024-05-01
Last modified: 2026-06-17

Description

libmodbus v3.1.10 has a heap-based buffer overflow vulnerability in read_io_status function in src/modbus.c.

Frequently asked questions

What is CVE-2023-26793?: libmodbus v3.1.10 has a heap-based buffer overflow vulnerability in read_io_status function in src/modbus.c.
How severe is CVE-2023-26793?: CVE-2023-26793 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-2023-26793 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26793?: CVE-2023-26793 affects Libmodbus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-26793?: 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.
Does CVE-2023-26793 have an EU (EUVD) identifier?: Yes. CVE-2023-26793 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-30586.
When was CVE-2023-26793 published?: CVE-2023-26793 was published on 2024-05-01 and last updated on 2026-06-17.

References

https://github.com/stephane/libmodbus/issues/683

Affected products (1)

cpe:2.3:a:libmodbus:libmodbus:3.1.10:*:*:*:*:*:*:*

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