Vulnerability · CVE-2025-61661
A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component.
Published Nov 18, 2025 · catalog updated Sep 1, 2026 · GNU
Last checked Oct 26, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2025-61661. EPSS is 0.21%. Act only if a listed version of GNU is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2026-4631 · Critical · known exploited
- CVE-2025-54770 · Medium
- CVE-2025-61664 · Medium
- CVE-2025-61663 · Medium
- CVE-2025-54771 · Medium
- Severity
- Medium4.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.21%
- Remediation
- Advisory link
- Affected products
- vendor GNU grub2 0 ≤2.14
A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component. This flaw occurs because the bootloader mishandles string conversion when reading information from a USB device, allowing an attacker to exploit inconsistent length values. A local attacker can connect a maliciously configured USB device during the boot sequence to trigger this issue. A successful exploitation may lead GRUB to crash, leading to a Denial of Service. Data corruption may be also possible, although given the complexity of the exploit the impact is most likely limited.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor GNU grub2 0 ≤2.140 ≤2.14
How to fix CVE-2025-61661
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
Seen in 0 ≤2.14
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-61661. EPSS is 0.21%. Act only if a listed version of GNU is installed.
Which versions are affected?
Compare what you have installed with GNU grub2 0 ≤2.14 0 ≤2.14. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.21%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Nov 18, 2025 · EUVD
Detected
A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component. This flaw occurs because the bootloader mishandles string conversion when reading information from a USB device, allowing an attacker to exploit inconsistent length values. A local attacker can connect a maliciously configured USB device during the boot sequence to trigger this issue. A successful exploitation ma
Sep 1, 2026 · EUVD
Updated
A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component. This flaw occurs because the bootloader mishandles string conversion when reading information from a USB device, allowing an attacker to exploit inconsistent length values. A local attacker can connect a maliciously configured USB device during the boot sequence to trigger this issue. A successful exploitation ma
Sources
- CVE.orgVulnerability recordCVE-2025-61661
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-61661
30-day exploitation probability 0.21%
first.org - EUVDVulnerability recordEUVD-2025-198081
A vulnerability has been identified in the GRUB (Grand Unified Bootloader) component. This flaw occurs because the bootloader mishandles string conversion when reading information from a USB device, allowing an attacker to exploit inconsistent length values. A local attacker can
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 26, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 26, 2026
- CVE.orgOct 26, 2026
- EUVDOct 26, 2026