CVE-2025-38626: f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode
Noroxi assessment
Priority: Monitor (action score 22/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 1005a3ca28e90c7a64fa43023f866b960a60f791, 264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5, 385e64a0744584397b4b52b27c96703516f39968; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1.
Low priority for now. Upgrade to Linux Linux 1005a3ca28e90c7a64fa43023f866b960a60f791, 264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5, 385e64a0744584397b4b52b27c96703516f39968; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode w/ "mode=lfs" mount option, generic/299 will cause system panic as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.c:2835! Call Trace: <TASK> f2fs_allocate_data_block+0x6f4/0xc50 f2fs_map_blocks+0x970/0x1550 f2fs_iomap_begin+0xb2/0x1e0 iomap_iter+0x1d6/0x430 __iomap_dio_rw+0x208/0x9a0 f2fs_file_write_iter+0x6b3/0xfa0 aio_write+0x15d/0x2e0 io_submit_one+0x55e/0xab0 __x64_sys_io_submit+0xa5/0x230 do_syscall_64+0x84/0x2f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0010:new_curseg+0x70f/0x720 The root cause of we run out-of-space is: in f2fs_map_blocks(), f2fs may trigger foreground gc only if it allocates any physical block, it will be a little bit later when there is multiple threads writing data w/ aio/dio/bufio method in parallel, since we always use OPU in lfs mode, so f2fs_map_blocks() does block allocations aggressively. In order to fix this issue, let's give a chance to trigger foreground gc in prior to block allocation in f2fs_map_blocks().
- Published
- Aug 22, 2025
- Updated
- Jun 17, 2026
- EPSS
- 0.1% · 6th percentile
- CWE
- —
Report tools
Action score
22
Monitor
Low priority for now.
- CVSS
- 22 / 40 · 5.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel4.8 and later · before 6.6.102
- linux linux kernel6.7 and later · before 6.12.42
- linux linux kernel6.13 and later · before 6.15.10
- linux linux kernel6.16 and later · before 6.16.1
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 4.8affected
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before c737047f4665232d1e26b3620bc62df334545451affected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before d2f280f43a2a9d918fd23169ff3a6f3b65c7cec5affected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before f289690f50a01c3e085d87853392d5b7436a4ceeaffected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before 82765ce5c7a56f9309ee45328e763610eaf11253affected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before 264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5affected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before 385e64a0744584397b4b52b27c96703516f39968affected · git
- 36abef4e796d382e81a0c2d21ea5327481dd7154 and later · before 1005a3ca28e90c7a64fa43023f866b960a60f791affected · git
- before 4.8not affected · semver
- 5.15.209 and later · up to and including 5.15.*not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.170-1 | 6.1.170-1 |
| Debian:13 | linux | before 6.12.43-1 | 6.12.43-1 |
| Debian:14 | linux | before 6.16.3-1 | 6.16.3-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2025-38624Aug 22, 2025 · PCI: pnv_php: Clean up allocated IRQs on unplug22Monitor
- ← EarlierCVE-2025-38625Aug 22, 2025 · vfio/pds: Fix missing detach_ioas op22Monitor
- Later →CVE-2025-38627Aug 22, 2025 · f2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic31Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 1005a3ca28e90c7a64fa43023f866b960a60f791 | Vendor (CNA) |
| Linux Linux | 264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5 | Vendor (CNA) |
| Linux Linux | 385e64a0744584397b4b52b27c96703516f39968 | Vendor (CNA) |
| Linux Linux | 82765ce5c7a56f9309ee45328e763610eaf11253 | Vendor (CNA) |
| Linux Linux | c737047f4665232d1e26b3620bc62df334545451 | Vendor (CNA) |
| Linux Linux | d2f280f43a2a9d918fd23169ff3a6f3b65c7cec5 | Vendor (CNA) |
| Linux Linux | f289690f50a01c3e085d87853392d5b7436a4cee | Vendor (CNA) |
| azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 | 6.6.104.2-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| debian:linux | 6.1.170-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (6 more)Show less
- git.kernel.org/stable/c/264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5
- git.kernel.org/stable/c/385e64a0744584397b4b52b27c96703516f39968
- git.kernel.org/stable/c/82765ce5c7a56f9309ee45328e763610eaf11253
- git.kernel.org/stable/c/c737047f4665232d1e26b3620bc62df334545451
- git.kernel.org/stable/c/d2f280f43a2a9d918fd23169ff3a6f3b65c7cec5
- git.kernel.org/stable/c/f289690f50a01c3e085d87853392d5b7436a4cee
Vendor advisories and official records. Exploit/PoC links are deliberately left out.