VulnerabilityPublished 24 Sep 2026Updated 19 Oct 2026

CVE-2026-93206: Linux kernel · PCI/proc: Use file_ns_capable() when checking config space read access

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in f82f53e75eff382fc8f56b73279b54f7cf5a5c65 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 12:55 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in f82f53e75eff382fc8f56b73279b54f7cf5a5c65, e7730acd6a01c5931a3afb83639810ff2fb9cc92, c2d4174f492458ecdcdef309243624999612d526 +5

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < f82f53e75eff382fc8f56b73279b54f7cf5a5c65	Fixed in f82f53e75eff382fc8f56b73279b54f7cf5a5c65
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < e7730acd6a01c5931a3afb83639810ff2fb9cc92	Fixed in e7730acd6a01c5931a3afb83639810ff2fb9cc92
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < c2d4174f492458ecdcdef309243624999612d526	Fixed in c2d4174f492458ecdcdef309243624999612d526
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 53407535d49ec034e476121020b5c878f0d92e18	Fixed in 53407535d49ec034e476121020b5c878f0d92e18
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 77272b7fd0e472086fd626a1fcd11da625822cc2	Fixed in 77272b7fd0e472086fd626a1fcd11da625822cc2
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 6351e94076329dab517ea94c115e15c4d8459381	Fixed in 6351e94076329dab517ea94c115e15c4d8459381

Description

In the Linux kernel, the following vulnerability has been resolved: PCI/proc: Use file_ns_capable() when checking config space read access proc_bus_pci_read() decides how much of the config space is readable based on capable(CAP_SYS_ADMIN), which checks the credentials of the task calling read(), not the credentials of the process that opened the file. The sysfs equivalent, pci_read_config(), has checked the credentials of the opening process since commit de139a339395 ("pci: check caps from sysfs file open to read device dependent config space"), so a privileged process can open the config space file and pass the file descriptor to an unprivileged process (for example, a process running a KVM guest with an assigned device), which can then read the entire config space. The check was subsequently routed through the LSM framework in commit 47970b1b2aa6 ("pci: use security_capable() when checking capablities during config space read") and converted to the dedicated helper in commit ab0fa82b2df9 ("pci-sysfs: use proper file capability helper function"). Thus, the two interfaces check the same capability against different credentials. Checking the credentials of the task calling read() makes the outcome depend on who reads rather than who opened, so the restriction is bypassed whenever a more privileged process reads through the descriptor. Checking the credentials recorded in file->f_cred settles the decision at open() time and ties it to the file, where it cannot change with the caller. Use file_ns_capable() to check CAP_SYS_ADMIN against the credentials in effect when the file was opened, bringing the procfs interface in line with the sysfs behaviour. As a result, a file descriptor opened by a privileged process and passed to an unprivileged one now allows the entire config space to be read through procfs, matching sysfs.

References

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