CVE-2026-68145: Linux kernel · iomap: fix out-of-bounds bitmap_set() with zero-length range
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in fb4fad9105c88b1d82f1b3c39e3b6abea8249af6 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:30 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in fb4fad9105c88b1d82f1b3c39e3b6abea8249af6, c5b6a48a8a716a7730e39af1cad083dc4ec955ce, 48829622212f6b8f49155889aecc818ba28ba680 +2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 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.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: iomap: fix out-of-bounds bitmap_set() with zero-length range ifs_set_range_dirty() and ifs_set_range_uptodate() compute last_blk as (off + len - 1) >> i_blkbits. When off is 0 and len is 0, the unsigned subtraction underflows to SIZE_MAX, producing a huge last_blk and nr_blks value that causes bitmap_set() to write far beyond the ifs->state allocation. Regarding ifs_set_range_uptodate(), it is temporarily safe because len cannot be passed in as 0. However, for ifs_set_range_dirty() this is reachable from __iomap_write_end(): when copy_folio_from_iter_atomic() returns 0 (e.g. user buffer fault) and the folio is already uptodate, the guard at the top of __iomap_write_end() does not trigger because !folio_test_uptodate() is false, and iomap_set_range_dirty() is called with copied == 0. Add a !len guard to both functions before the computation, so that a zero-length range is a no-op.
References
- git.kernel.org/stable/c/48829622212f6b8f49155889aecc818ba28ba680 (opens in a new tab)
- git.kernel.org/stable/c/fb4fad9105c88b1d82f1b3c39e3b6abea8249af6 (opens in a new tab)
- git.kernel.org/stable/c/7037e7bdcd26f46c080b8ce307dee5cb471c4b7c (opens in a new tab)
- git.kernel.org/stable/c/c5b6a48a8a716a7730e39af1cad083dc4ec955ce (opens in a new tab)
- git.kernel.org/stable/c/9c7d8f7c8994c790fca501dc45ce66e7356cbe05 (opens in a new tab)