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NVD / CVE Program· CNA Linux

CVE-2026-64254: NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.11% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 06f6dd2ff2bd07eaf7178a807407ff27e85122b4, 81371dbd23601f67f01372817fdbab42c5601e43, 9764a786ba98db58f0725913c369e721253aba33.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 06f6dd2ff2bd07eaf7178a807407ff27e85122b4, 81371dbd23601f67f01372817fdbab42c5601e43, 9764a786ba98db58f0725913c369e721253aba33 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR When BAR_PEER_SPAD and BAR_CONFIG share one PCI BAR, the module teardown path ends up calling pci_iounmap() on the same iomem with some offset, which is unnecessary and triggers a kernel warning like the following: Trying to vunmap() nonexistent vm area (0000000069a5ffe8) WARNING: mm/vmalloc.c:3470 at vunmap+0x58/0x68, CPU#5: modprobe/2937 [...] Call trace: vunmap+0x58/0x68 (P) iounmap+0x34/0x48 pci_iounmap+0x2c/0x40 ntb_epf_pci_remove+0x44/0x80 [ntb_hw_epf] pci_device_remove+0x48/0xf8 device_remove+0x50/0x88 device_release_driver_internal+0x1c8/0x228 driver_detach+0x50/0xb0 bus_remove_driver+0x74/0x100 driver_unregister+0x34/0x68 pci_unregister_driver+0x34/0xa0 ntb_epf_pci_driver_exit+0x14/0xfe0 [ntb_hw_epf] [...] Fix it by unmapping only when PEER_SPAD and CONFIG use difference bars.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Jul 24, 2026
Updated
Aug 17, 2026
EPSS
0.1% · 1th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel6.0 and later · before 6.1.177
  • linux linux kernel6.2 and later · before 6.6.144
  • linux linux kernel6.7 and later · before 6.12.95
  • linux linux kernel6.13 and later · before 6.18.38
  • linux linux kernel6.19 and later · before 7.1.3

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 6.0affected
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before eb47b9bffd07a47b84910847cb5ea066ce184055affected · git
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before 06f6dd2ff2bd07eaf7178a807407ff27e85122b4affected · git
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before a4be4a1308f02bff79a30eea2d04ead5b63685f2affected · git
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before 81371dbd23601f67f01372817fdbab42c5601e43affected · git
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before 9764a786ba98db58f0725913c369e721253aba33affected · git
    • e75d5ae8ab88b7ffb3d1d56124b003f3555f74b4 and later · before d876153680e3d721d385e554def919bce3d18c74affected · git
    • before 6.0not affected · semver
    • 6.1.177 and later · up to and including 6.1.*not affected · semver
    • 6.6.144 and later · up to and including 6.6.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.177-16.1.177-1
Debian:13linuxbefore 6.12.95-16.12.95-1
Debian:14linuxbefore 7.1.3-17.1.3-1
openSUSE:Tumbleweedkernel-sourcebefore 7.1.7-1.17.1.7-1.1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-64251Jul 24, 2026 · pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()
    31Monitor
  • ← EarlierCVE-2026-64252Jul 24, 2026 · MIPS: DEC: Prevent initial console buffer from landing in XKPHYS
    22Monitor
  • Later →CVE-2026-64210Jul 24, 2026 · net/mlx5e: xsk: Fix unlocked writing to ICOSQ
    30Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux06f6dd2ff2bd07eaf7178a807407ff27e85122b4Vendor (CNA)
Linux Linux81371dbd23601f67f01372817fdbab42c5601e43Vendor (CNA)
Linux Linux9764a786ba98db58f0725913c369e721253aba33Vendor (CNA)
Linux Linuxa4be4a1308f02bff79a30eea2d04ead5b63685f2Vendor (CNA)
Linux Linuxd876153680e3d721d385e554def919bce3d18c74Vendor (CNA)
Linux Linuxeb47b9bffd07a47b84910847cb5ea066ce184055Vendor (CNA)
debian:linux6.1.177-1 · Debian:12Package registry (OSV)
opensuse:kernel-source7.1.7-1.1 · openSUSE:TumbleweedPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-5295230 days apartiommu: Fix WARN_ON in __iommu_group_set_domain_nofail() due to reset
    35Monitor
  • CVE-2026-3173984 days apartcrypto: tegra - Add missing CRYPTO_ALG_ASYNC
    35Monitor
  • CVE-2026-4611757 days apartRDMA/mana: Remove user triggerable WARN_ON() in mana_ib_create_qp_rss()
    31Monitor
  • CVE-2026-31398112 days apartmm/rmap: fix incorrect pte restoration for lazyfree folios
    31Monitor
  • CVE-2025-39803312 days apartscsi: ufs: core: Remove WARN_ON_ONCE() call from ufshcd_uic_cmd_compl()
    31Monitor
  • CVE-2026-5295430 days apartlibceph: handle rbtree insertion error in decode_choose_args()
    30Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-617 · Reachable Assertion

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records