How severe is CVE-2009-4128?

CVE-2009-4128 has a CVSS 2.0 base score of 7.2, rated high severity.

Is CVE-2009-4128 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-4128?

CVE-2009-4128 affects Gnu Grub 2. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-4128?

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-2009-4128 published?

CVE-2009-4128 was published on 2009-12-01 and last updated on 2026-06-16.

CVE-2009-4128

CVE-2009-4128 is a high-severity vulnerability in Gnu Grub 2 with a CVSS 2.0 base score of 7.2. 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-287.

Key facts

Severity: High (CVSS 2.0 base score 7.2)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Gnu Grub 2
Published: 2009-12-01
Last modified: 2026-06-16

Description

GNU GRand Unified Bootloader (GRUB) 2 1.97 only compares the submitted portion of a password with the actual password, which makes it easier for physically proximate attackers to conduct brute force attacks and bypass authentication by submitting a password whose length is 1.

Frequently asked questions

What is CVE-2009-4128?: GNU GRand Unified Bootloader (GRUB) 2 1.97 only compares the submitted portion of a password with the actual password, which makes it easier for physically proximate attackers to conduct brute force attacks and bypass authentication by submitting a password whose length is 1.
How severe is CVE-2009-4128?: CVE-2009-4128 has a CVSS 2.0 base score of 7.2, rated high severity.
Is CVE-2009-4128 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4128?: CVE-2009-4128 affects Gnu Grub 2. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-4128?: 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-2009-4128 published?: CVE-2009-4128 was published on 2009-12-01 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:gnu:grub_2:1.97:*:*:*:*:*:*:*

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