CVE-2026-63818
Linux f2fs checkpoint parsing bug can crash kernel during mount
Is CVE-2026-63818 being exploited?
Not confirmed. CVE-2026-63818 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.14% probability of exploitation in the next 30 days.
How severe is CVE-2026-63818?
CVE-2026-63818 is rated High with a CVSS score of 8.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-63818?
Yes. A fix has been recorded for CVE-2026-63818. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-63818 affect?
CVE-2026-63818 affects Linux kernel with f2fs enabled, Android devices using f2fs, Embedded/IoT devices using f2fs. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-63818?
Apply kernel updates that fix CVE-2026-63818; avoid mounting untrusted f2fs images
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Malformed f2fs checkpoint entry_count can drive orphan recovery into a kernel panic, causing DoS and possible filesystem corruption requiring fsck.
Patch when possible
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < 210c210c92d78fdf5051bc55c5c69044b1a2150a
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < ad101d15716f5a24d1fa82a849f80430c805a3dd
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < d18c81f5d0ecd5796aa47d66d98f2dd54d8d0f70
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < d2f236196d542ccd8505736e41c3a1d3f0305f6f
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < 550511a2470f6d204fa07b331f048bd2d3c51280
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < 8aad54746c251f2c2370118df766c0c82e2d2091
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < 2e12381d4495dc8b0ff042c6856022b2e359835c
- affected>= 127e670abfa7fa150f6550d620ded930f5bdb4e7 and < 846c499a65816d13f1186e3090e825e8bb8bcb8b
- affected3.8
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.