CVE Intelligence
Unknown

CVE-2022-50579 — arm64: ftrace: fix module PLTs with mcount

In the Linux kernel, the following vulnerability has been resolved: arm64: ftrace: fix module PLTs with mcount Li Huafei reports that mcount-based ftrace with module PLTs was broken by commit: a6253579977e4c6f ("arm64: ftrace: consistently handle PLTs.") When a module PLTs are used and a module is loaded sufficiently far away from the kernel, we'll create PLTs for any branches which are out-of-range. These are separate from the special ftrace trampoline PLTs, which the module PLT code doesn't directly manipulate. When mcount is in use this is a problem, as each mcount callsite in a module will be initialized to point to a module PLT, but since commit a6253579977e4c6f ftrace_make_nop() will assume that the callsite has been initialized to point to the special ftrace trampoline PLT, and ftrace_find_callable_addr() rejects other cases. This means that when ftrace tries to initialize a callsite via ftrace_make_nop(), the call to ftrace_find_callable_addr() will find that the `_mcount` stub is out-of-range and is not handled by the ftrace PLT, resulting in a splat: | ftrace_test: loading out-of-tree module taints kernel. | ftrace: no module PLT for _mcount | ------------[ ftrace bug ]------------ | ftrace failed to modify | [<ffff800029180014>] 0xffff800029180014 | actual: 44:00:00:94 | Initializing ftrace call sites | ftrace record flags: 2000000 | (0) | expected tramp: ffff80000802eb3c | ------------[ cut here ]------------ | WARNING: CPU: 3 PID: 157 at kernel/trace/ftrace.c:2120 ftrace_bug+0x94/0x270 | Modules linked in: | CPU: 3 PID: 157 Comm: insmod Tainted: G O 6.0.0-rc6-00151-gcd722513a189-dirty #22 | Hardware name: linux,dummy-virt (DT) | pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : ftrace_bug+0x94/0x270 | lr : ftrace_bug+0x21c/0x270 | sp : ffff80000b2bbaf0 | x29: ffff80000b2bbaf0 x28: 0000000000000000 x27: ffff0000c4d38000 | x26: 0000000000000001 x25: ffff800009d7e000 x24: ffff0000c4d86e00 | x23: 0000000002000000 x22: ffff80000a62b000 x21: ffff8000098ebea8 | x20: ffff0000c4d38000 x19: ffff80000aa24158 x18: ffffffffffffffff | x17: 0000000000000000 x16: 0a0d2d2d2d2d2d2d x15: ffff800009aa9118 | x14: 0000000000000000 x13: 6333626532303830 x12: 3030303866666666 | x11: 203a706d61727420 x10: 6465746365707865 x9 : 3362653230383030 | x8 : c0000000ffffefff x7 : 0000000000017fe8 x6 : 000000000000bff4 | x5 : 0000000000057fa8 x4 : 0000000000000000 x3 : 0000000000000001 | x2 : ad2cb14bb5438900 x1 : 0000000000000000 x0 : 0000000000000022 | Call trace: | ftrace_bug+0x94/0x270 | ftrace_process_locs+0x308/0x430 | ftrace_module_init+0x44/0x60 | load_module+0x15b4/0x1ce8 | __do_sys_init_module+0x1ec/0x238 | __arm64_sys_init_module+0x24/0x30 | invoke_syscall+0x54/0x118 | el0_svc_common.constprop.4+0x84/0x100 | do_el0_svc+0x3c/0xd0 | el0_svc+0x1c/0x50 | el0t_64_sync_handler+0x90/0xb8 | el0t_64_sync+0x15c/0x160 | ---[ end trace 0000000000000000 ]--- | ---------test_init----------- Fix this by reverting to the old behaviour of ignoring the old instruction when initialising an mcount callsite in a module, which was the behaviour prior to commit a6253579977e4c6f.

Published Oct 22, 2025 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+2

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.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.21%
ahead of 11% of scored CVEs · Oct 15, 2026
Affects
Linux
Linux
CVSS base
—
Score not published yet.

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.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ bc28fde90937a920f7714ec4408269cac744f796 and < 657de36c72f57fa172a66b06f826b3f5bc56f42e≥ db73aa9466338ec821ed2a0b01721fe4d06876b1 and < 6c93b683cedaef745884cb9d554d02ed6266b897≥ a6253579977e4c6f7818eeb05bf2bc65678a7187 and < 0f77b6b2ba70d7c9d69ef39694e283ded9f8b5f2≥ a6253579977e4c6f7818eeb05bf2bc65678a7187 and < 985432303cf7d4804fb2c2fdfbf0466a796d68c3≥ a6253579977e4c6f7818eeb05bf2bc65678a7187 and < 8cfb08575c6d4585f1ce0deeb189e5c824776b04version dcecc96ed16f73417de5550f384e348c9d56f279≥ 5.10.124 and < 5.10.150≥ 5.15.49 and < 5.15.75
and 2 more ≥ 5.18.6 and < 5.19version 5.19
Vulnerable CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.21%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Not enough vector or weakness data: use the affected application’s logs as a starting point.
application logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Record published
    Oct 13, 2026
  • Affected products added · linux/linux
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Deferred
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • 2025
  • CVE published
    Oct 22, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

5 on the record

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

  • CVE-2026-99999 ipv4: validate checksum_start before completing checksum 20h
  • CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 20h
  • CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
  • CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
  • CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
  • CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d

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 CVSS score published by NVD, the CNA, CISA or GitHub so far.
  • 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-2022-50579 is "arm64: ftrace: fix module PLTs with mcount", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% 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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