CVE-2026-80806: Linux kernel · ext4: don't enable DAX on new encrypted files
Source GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 4 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: don't enable DAX on new encrypted files Currently, when a new encrypted regular file is created, the call to ext4_set_inode_flags(inode, init=true) in __ext4_new_inode() is made before EXT4_INODE_ENCRYPT is set. As a result, it can set S_DAX if the filesystem is mounted with "-o dax=always". EXT4_INODE_ENCRYPT then actually gets set a bit later in __ext4_new_inode(), when it calls fscrypt_set_context() which calls ext4_set_context(). ext4_set_context() sets EXT4_INODE_ENCRYPT and calls ext4_set_inode_flags(inode, init=false) to set S_ENCRYPTED too. This was intended to clear S_DAX as well. However, this was broken by commit 043546e46dc7 ("fs/ext4: Only change S_DAX on inode load"). This causes data written to the file to bypass encryption, also causing xfstests failures such as generic/548 (when "-o dax=always" is used). Fix this by simplifying the flow by making __ext4_new_inode() set EXT4_INODE_ENCRYPT earlier. This makes it take effect in ext4_set_inode_flags(inode, init=true), making S_DAX never be set. Similarly, make EXT4_STATE_MAY_INLINE_DATA never be set in the first place on new encrypted inodes. Then it doesn't need to be cleared. As a result of these simplifications, ext4_set_context() no longer needs to change inode flags or state when 'handle != NULL'. Remove that too.
References
- nvd.nist.gov/vuln/detail/CVE-2026-80806 (opens in a new tab)
- git.kernel.org/stable/c/3392391b363a63ebb531d45318a729b1c998565b (opens in a new tab)
- git.kernel.org/stable/c/458776af0061afec1014cb3cd0061e282e482e83 (opens in a new tab)
- git.kernel.org/stable/c/5959cad3cfa852ec07bbdaf9c17f4838a94a8e6c (opens in a new tab)
- git.kernel.org/stable/c/a13f61ba9b2a7a4ff1f140949ccfad23c5313757 (opens in a new tab)
- git.kernel.org/stable/c/add98959b220935b243170214c787bc03044a44d (opens in a new tab)
- git.kernel.org/stable/c/da32af420d6d466e247c43ac0b829edeac7ae0ad (opens in a new tab)
- git.kernel.org/stable/c/e27bae352158c007143d5bb50f3af33a177c0a37 (opens in a new tab)
- git.kernel.org/stable/c/ed1cd834da65db127f1c30ff67e78f14825a06c1 (opens in a new tab)
- git.kernel.org/stable/c/f53b325068bca0b238c3e0d2eb7de9b1f2268cab (opens in a new tab)