CVE Intelligence
Medium

CVE-2025-39907 — mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC buffer

In the Linux kernel, the following vulnerability has been resolved: mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC buffer Avoid below overlapping mappings by using a contiguous non-cacheable buffer. [ 4.077708] DMA-API: stm32_fmc2_nfc 48810000.nand-controller: cacheline tracking EEXIST, overlapping mappings aren't supported [ 4.089103] WARNING: CPU: 1 PID: 44 at kernel/dma/debug.c:568 add_dma_entry+0x23c/0x300 [ 4.097071] Modules linked in: [ 4.100101] CPU: 1 PID: 44 Comm: kworker/u4:2 Not tainted 6.1.82 #1 [ 4.106346] Hardware name: STMicroelectronics STM32MP257F VALID1 SNOR / MB1704 (LPDDR4 Power discrete) + MB1703 + MB1708 (SNOR MB1730) (DT) [ 4.118824] Workqueue: events_unbound deferred_probe_work_func [ 4.124674] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 4.131624] pc : add_dma_entry+0x23c/0x300 [ 4.135658] lr : add_dma_entry+0x23c/0x300 [ 4.139792] sp : ffff800009dbb490 [ 4.143016] x29: ffff800009dbb4a0 x28: 0000000004008022 x27: ffff8000098a6000 [ 4.150174] x26: 0000000000000000 x25: ffff8000099e7000 x24: ffff8000099e7de8 [ 4.157231] x23: 00000000ffffffff x22: 0000000000000000 x21: ffff8000098a6a20 [ 4.164388] x20: ffff000080964180 x19: ffff800009819ba0 x18: 0000000000000006 [ 4.171545] x17: 6361727420656e69 x16: 6c6568636163203a x15: 72656c6c6f72746e [ 4.178602] x14: 6f632d646e616e2e x13: ffff800009832f58 x12: 00000000000004ec [ 4.185759] x11: 00000000000001a4 x10: ffff80000988af58 x9 : ffff800009832f58 [ 4.192916] x8 : 00000000ffffefff x7 : ffff80000988af58 x6 : 80000000fffff000 [ 4.199972] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000 [ 4.207128] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000812d2c40 [ 4.214185] Call trace: [ 4.216605] add_dma_entry+0x23c/0x300 [ 4.220338] debug_dma_map_sg+0x198/0x350 [ 4.224373] __dma_map_sg_attrs+0xa0/0x110 [ 4.228411] dma_map_sg_attrs+0x10/0x2c [ 4.232247] stm32_fmc2_nfc_xfer.isra.0+0x1c8/0x3fc [ 4.237088] stm32_fmc2_nfc_seq_read_page+0xc8/0x174 [ 4.242127] nand_read_oob+0x1d4/0x8e0 [ 4.245861] mtd_read_oob_std+0x58/0x84 [ 4.249596] mtd_read_oob+0x90/0x150 [ 4.253231] mtd_read+0x68/0xac

Published Oct 1, 2025 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · 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)+1
  • Technical severity (medium)+3

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
0.15%
ahead of 4% of scored CVEs · Oct 19, 2026
Affects
Debian
Debian Linux and 2 more
CVSS base
5.5
Medium · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)

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 (Debian Debian Linux, Linux Linux, Linux Linux Kernel).
  2. Apply the fixed version or the patch documented under Remediation.
  3. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Debian Debian Linux version 11.0 Vulnerable NIST National Vulnerability Database
Linux Linux version 5.1≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < 513c40e59d5a414ab763a9c84797534b5e8c208d≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < f6fd98d961fa6f97347cead4f08ed862cbbb91ff≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < 26adba1e7d7924174e15a3ba4b1132990786300b≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < 06d8ef8f853752fea88c8d5bb093a40e71b330cf≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < 75686c49574dd5f171ca682c18717787f1d8d55e≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < e32a2ea52b51368774d014e5bcd9b86110a2b727≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < dfe2ac47a6ee0ab50393694517c54ef1e276dda3
and 1 more ≥ 2cd457f328c100bc98e36d55fe210e9ab067c704 and < dc1c6e60993b93b87604eb11266ac72e1a3be9e0
Vulnerable CVE Program (cve.org) e CISA ADP
Linux Linux Kernel version 6.17-rc4version 6.17-rc5version 6.17-rc3version 6.17-rc2version 6.17-rc1≥ 6.13 and < 6.16.8≥ 6.7 and < 6.12.48≥ 6.2 and < 6.6.107
and 4 more ≥ 5.16 and < 6.1.153≥ 5.11 and < 5.15.194≥ 5.5 and < 5.10.245≥ 5.1 and < 5.4.300
Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
5.5 CVSS 3.1 Medium 1.8 3.6 nvd@nist.gov via NIST National Vulnerability Database
5.5 CVSS 3.1 Medium — — GitHub, Inc. via GitHub Security Advisories
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)

Detection

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

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · linux/linux
    Oct 19, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 19, 2026
  • Fix documented
    Oct 19, 2026 · NIST National Vulnerability Database
  • Affected products added · linux/linux kernel, debian/debian linux
    Oct 19, 2026 · NIST National Vulnerability Database
  • CVSS changed · 5.5
    Oct 19, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 19, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 19, 2026 · Alertas do Telegram
  • 2025
  • CVE published
    Oct 1, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 19, 2026 – Oct 19, 2026
  • 1× Official description updated · Oct 19, 2026 – Oct 19, 2026

References

11 on the record

Elsewhere on this site

Debian
every CVE for this vendor

Related CVEs (same products)

  • Unknown CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 1d
  • Unknown CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 1d
  • Unknown CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 1d
  • Unknown CVE-2026-98865 sched_ext: Don't run ops.dequeue() with a DSQ lock held 1d
  • Unknown CVE-2026-98864 sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task 1d
  • Unknown CVE-2026-98863 KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails 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 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-2025-39907 is "mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC buffer", rated Medium. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.15% 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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