CVE-2026-53165
Last modified
CVE-2026-53165 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: iomap: avoid potential null folio->mapping deref during error reporting When a buffered read fails, iomap_finish_folio_read() reports the error with fserror_report_io(folio->mapping->host, ...). This is called after ifs->read_bytes_pending has been decremented by the bytes attempted to be read. For a folio split across multiple read completions, the folio is only guaranteed to stay locked while read_bytes_pending > 0. EPSS estimates a 0.36% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: iomap: avoid potential null folio->mapping deref during error reporting When a buffered read fails, iomap_finish_folio_read() reports the error with fserror_report_io(folio->mapping->host, ...). This is called after ifs->read_bytes_pending has been decremented by the bytes attempted to be read. For a folio split across multiple read completions, the folio is only guaranteed to stay locked while read_bytes_pending > 0. Once iomap_finish_folio_read() decrements read_bytes_pending, another in-flight read can complete and end the read on the folio, which unlocks it. This allows truncate logic to run and detach the folio (set folio->mapping to NULL). The error reporting path then can dereference a NULL folio->mapping. As reported by Sam Sun, this is the race that can occur: CPU0: failed completion CPU1: final completion CPU2: truncate ----------------------- ---------------------- -------------- read_bytes_pending -= len finished = false /* preempted before fserror_report_io() */ read_bytes_pending -= len finished = true folio_end_read() truncate clears folio->mapping fserror_report_io( folio->mapping->host, ...) ^ NULL deref Fix this by reporting the error first before decrementing ifs->read_bytes_pending.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 7.0, < 7.0.13 | — |
| Linux | Linux Kernel | 7.1 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-53165?
How severe is CVE-2026-53165?
How do I fix CVE-2026-53165?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-5316A vulnerability was identified in Nothings stb up to 1.22. T…6.5
- CVE-2026-53160In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-53161In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-53162In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-53163In the Linux kernel, the following vulnerability has been re…5.5
- CVE-2026-53164In the Linux kernel, the following vulnerability has been re…5.5
- CVE-2026-53166Rejected reason: This CVE ID has been rejected or withdrawn …
- CVE-2026-53167In the Linux kernel, the following vulnerability has been re…5.5
- CVE-2026-53168In the Linux kernel, the following vulnerability has been re…5.5
- CVE-2026-53169In the Linux kernel, the following vulnerability has been re…5.5
- CVE-2026-5317A security flaw has been discovered in Nothings stb up to 1.…8.8
- CVE-2026-53170In the Linux kernel, the following vulnerability has been re…8.8
Are you affected by CVE-2026-53165?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
