grub2: Use After Free
CVE-2025-61662 is a high-severity use after free vulnerability in grub2 from GNU, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected grub2 versions: 2.14 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of grub2 you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 1 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA (redhat.com) |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
A Use-After-Free vulnerability has been discovered in GRUB's gettext module. This flaw stems from a programming error where the gettext command remains registered in memory after its module is unloaded. An attacker can exploit this condition by invoking the orphaned command, causing the application to access a memory location that is no longer valid. An attacker could exploit this vulnerability to cause grub to crash, leading to a Denial of Service. Possible data integrity or confidentiality compromise is not discarded.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- openwall.com/lists/oss-security/2025/11/18/5Mailing List
Third-party and government advisories
- access.redhat.com/security/cve/CVE-2025-61662Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2414683Issue Tracking, Third Party Advisory
Other references
- access.redhat.com/errata/RHSA-2026:10097
- access.redhat.com/errata/RHSA-2026:14773
- access.redhat.com/errata/RHSA-2026:15087
- access.redhat.com/errata/RHSA-2026:17596
- access.redhat.com/errata/RHSA-2026:4648
- access.redhat.com/errata/RHSA-2026:4649
- access.redhat.com/errata/RHSA-2026:4652
- access.redhat.com/errata/RHSA-2026:4653
- access.redhat.com/errata/RHSA-2026:4654
- access.redhat.com/errata/RHSA-2026:4760
- access.redhat.com/errata/RHSA-2026:4822
- access.redhat.com/errata/RHSA-2026:4823
- access.redhat.com/errata/RHSA-2026:4830
- access.redhat.com/errata/RHSA-2026:4900
- access.redhat.com/errata/RHSA-2026:4998
Other vulnerabilities in grub2
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Recent Use After Free vulnerabilities
- 8.0 High severity
- 7.5 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Spotted an error? Tell us.