CVE-2026-98540
In the Linux kernel, the following vulnerability has been resolved: fprobe: Terminate the fgraph_data list when the reservation is not filled fprobe_fgraph_entry() reserves shadow stack space for every fprobe with an exit handler, but only fills it for those whose entry handler returns 0. fgraph_reserve_data() does not clear the area, so fprobe_return() parses the unused tail as headers left over from an earlier call, and an exit handler can run twice or despite its entry handler asking to skip it. Write a zero word after the last entry to terminate the walk. A zeroed slot does not decode to a NULL fprobe on the arches that encode the header into one unsigned long, since arch_decode_fprobe_header_fp() ORs in FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL for a zeroed slot.
Affected versions
Linux kernel versions
7.1
and later are affected. Fixed in
7.2.9,
7.3
and their respective stable series.
References
2 totalFrequently asked questions
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What is CVE-2026-98540?
CVE-2026-98540 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 7.1 onward and has been patched in 7.2.9 and 7.3. CVE-2026-98540 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-98540?
Yes. CVE-2026-98540 has been patched. Fixed versions include 7.2.9 and 7.3. If you are running Linux kernel 7.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-98540 actively exploited?
No. CVE-2026-98540 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.