CVE-2025-38549: efivarfs: Fix memory leak of efivarfs_fs_info in fs_context error paths
Vulnerability summary
CVE-2025-38549 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.5% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 33 · Related 33Timeline
- 16-08-2025PublishedVulnerability first disclosed.
- 11-05-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: efivarfs: Fix memory leak of efivarfs_fs_info in fs_context error paths When processing mount options, efivarfs allocates efivarfs_fs_info (sfi) early in fs_context initialization. However, sfi is associated with the superblock and typically freed when the superblock is destroyed. If the fs_context is released (final put) before fill_super is called—such as on error paths or during reconfiguration—the sfi structure would leak, as ownership never transfers to the superblock. Implement the .free callback in efivarfs_context_ops to ensure any allocated sfi is properly freed if the fs_context is torn down before fill_super, preventing this memory leak.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.15%
Chance of exploitation in the next 30 days
Percentile
5%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.15% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu121 products
- linux< 6.8.0-100.100
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 6.8.0-1046.49
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 5329aa5101f73c451bcd48deaf3f296685849d9c, < 816d36973467d1c9c08a48bdffe4675e219a2e84 | ≥ 5329aa5101f73c451bcd48deaf3f296685849d9c, < e9fabe7036bb8be6071f39dc38605508f5f57b20 | ≥ 5329aa5101f73c451bcd48deaf3f296685849d9c, < 64e135f1eaba0bbb0cdee859af3328c68d5b9789 | 6.7
- linux_kernel≥ 6.7, < 6.12.40 | ≥ 6.13, < 6.15.8 | 6.16:rc1 | 6.16:rc2 | 6.16:rc3 | 6.16:rc4 | 6.16:rc5 | 6.16:rc6
Debian1 product
- linux< 6.12.41-1 | < 6.16.3-1
3 vendors · 124 products