CVE-2026-68147 — fscrypt: Avoid dynamic allocation in fscrypt_get_devices()
In the Linux kernel, the following vulnerability has been resolved: fscrypt: Avoid dynamic allocation in fscrypt_get_devices() When a blk_crypto_key starts being used or is evicted, fs/crypto/ calls fscrypt_get_devices() to get the filesystem's list of block devices, then iterates over them and calls blk_crypto_config_supported(), blk_crypto_start_using_key(), or blk_crypto_evict_key() on each one. Currently, the block device pointers are placed in a dynamically allocated array. This dynamic allocation is problematic because: - It can fail, especially at the fscrypt_destroy_inline_crypt_key() call site when it's invoked for inode eviction under direct reclaim. - fscrypt_destroy_inline_crypt_key() doesn't handle the failure. It just zeroizes and frees the blk_crypto_key without calling blk_crypto_evict_key(). That causes a use-after-free. For now, let's fix this in the straightforward and easily-backportable way by switching to an on-stack array. Currently the fscrypt multi-device functionality is used only by f2fs, which has a hardcoded limit of 8 block devices. An on-stack array works fine for that. (Of course, this solution won't scale up to large number of block devices. For that we'd need a different solution, like moving the block device iteration into the filesystem. Or in the case of btrfs, which will only support blk-crypto-fallback, we should make it just call blk-crypto-fallback directly, so the block devices won't be needed.)
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+0
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < bab016bb80d74a9d1f7d4121a7fc1cb529b470e0≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < 4462ac3d90e897dda52ce4b6af2d526ddae835a8≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < 97a688563be71ec6fefc071aff69a66c69dbe244≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < 81ea8e8221853950c47dac7164f27c63a96f8f86≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < bc2d630296e0e049210ec05ff08459a6893ae749≥ 22e9947a4b2ba255888541bd0111cf00b9b16586 and < 6fe4e4b8259e1330945b5f3c9476e08473b8e0e8version 6.1 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- CVSS changed · 7.8
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
6 on the record
- git.kernel.org/stable/c/97a688563be71ec6fefc071aff69a66c69dbe244
- git.kernel.org/stable/c/6fe4e4b8259e1330945b5f3c9476e08473b8e0e8
- git.kernel.org/stable/c/81ea8e8221853950c47dac7164f27c63a96f8f86
- git.kernel.org/stable/c/bab016bb80d74a9d1f7d4121a7fc1cb529b470e0
- git.kernel.org/stable/c/4462ac3d90e897dda52ce4b6af2d526ddae835a8
- git.kernel.org/stable/c/bc2d630296e0e049210ec05ff08459a6893ae749
Elsewhere on this site
Related CVEs (same products)
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- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 2d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 2d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 2d
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Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-68147 is "fscrypt: Avoid dynamic allocation in fscrypt_get_devices()", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.14% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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