How severe is CVE-2026-5450?

CVE-2026-5450 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-2026-5450 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5450?

CVE-2026-5450 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5450?

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-2026-5450 have an EU (EUVD) identifier?

Yes. CVE-2026-5450 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-23978.

When was CVE-2026-5450 published?

CVE-2026-5450 was published on 2026-04-20 and last updated on 2026-06-17.

CVE-2026-5450

CVE-2026-5450 is a critical-severity vulnerability in Gnu Glibc 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-23978
Weakness: CWE-787
Affected product: Gnu Glibc
Published: 2026-04-20
Last modified: 2026-06-17

Description

Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.

Frequently asked questions

What is CVE-2026-5450?: Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.
How severe is CVE-2026-5450?: CVE-2026-5450 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-2026-5450 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5450?: CVE-2026-5450 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5450?: 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-2026-5450 have an EU (EUVD) identifier?: Yes. CVE-2026-5450 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-23978.
When was CVE-2026-5450 published?: CVE-2026-5450 was published on 2026-04-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*

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