In the Linux kernel, the following vulnerability has been resolved:
ARM: 9359/1: flush: check if the folio is reserved for no-mapping addresses
Since commit a4d5613c4dc6 ("arm: extend pfn_valid to take into account
freed memory map alignment") changes the semantics of pfn_valid() to check
presence of the memory map for a PFN. A valid page for an address which
is reserved but not mapped by the kernel[1], the system crashed during
some uio test with the following memory layout:
node 0: [mem 0x00000000c0a00000-0x00000000cc8fffff]
node 0: [mem 0x00000000d0000000-0x00000000da1fffff]
the uio layout is：0xc0900000, 0x100000
the crash backtrace like:
Unable to handle kernel paging request at virtual address bff00000
[...]
CPU: 1 PID: 465 Comm: startapp.bin Tainted: G O 5.10.0 #1
Hardware name: Generic DT based system
PC is at b15_flush_kern_dcache_area+0x24/0x3c
LR is at __sync_icache_dcache+0x6c/0x98
[...]
(b15_flush_kern_dcache_area) from (__sync_icache_dcache+0x6c/0x98)
(__sync_icache_dcache) from (set_pte_at+0x28/0x54)
(set_pte_at) from (remap_pfn_range+0x1a0/0x274)
(remap_pfn_range) from (uio_mmap+0x184/0x1b8 [uio])
(uio_mmap [uio]) from (__mmap_region+0x264/0x5f4)
(__mmap_region) from (__do_mmap_mm+0x3ec/0x440)
(__do_mmap_mm) from (do_mmap+0x50/0x58)
(do_mmap) from (vm_mmap_pgoff+0xfc/0x188)
(vm_mmap_pgoff) from (ksys_mmap_pgoff+0xac/0xc4)
(ksys_mmap_pgoff) from (ret_fast_syscall+0x0/0x5c)
Code: e0801001 e2423001 e1c00003 f57ff04f (ee070f3e)
---[ end trace 09cf0734c3805d52 ]---
Kernel panic - not syncing: Fatal exception
So check if PG_reserved was set to solve this issue.
[1]: https://lore.kernel.org/lkml/Zbtdue57RO0QScJM@linux.ibm.com/
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it