How severe is CVE-2023-6779?

CVE-2023-6779 has a CVSS 3.x base score of 8.2, 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 low, and availability high.

Is CVE-2023-6779 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-6779?

CVE-2023-6779 primarily affects Gnu Glibc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-6779?

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.

Does CVE-2023-6779 have an EU (EUVD) identifier?

Yes. CVE-2023-6779 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-58991.

When was CVE-2023-6779 published?

CVE-2023-6779 was published on 2024-01-31 and last updated on 2026-06-17.

CVE-2023-6779

CVE-2023-6779 is a high-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 8.2. 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.2)
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-58991
Weakness: CWE-787
Affected product: Gnu Glibc
Published: 2024-01-31
Last modified: 2026-06-17

Description

An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.

Frequently asked questions

What is CVE-2023-6779?: An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.
How severe is CVE-2023-6779?: CVE-2023-6779 has a CVSS 3.x base score of 8.2, 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 low, and availability high.
Is CVE-2023-6779 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-6779?: CVE-2023-6779 primarily affects Gnu Glibc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-6779?: 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.
Does CVE-2023-6779 have an EU (EUVD) identifier?: Yes. CVE-2023-6779 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-58991.
When was CVE-2023-6779 published?: CVE-2023-6779 was published on 2024-01-31 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*

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