Unknown

CVE-2026-68186 — binfmt_misc: set have_execfd only once the interpreter is opened

In the Linux kernel, the following vulnerability has been resolved: binfmt_misc: set have_execfd only once the interpreter is opened load_misc_binary() raises bprm->have_execfd as soon as it sees the 'O' (or 'C') flag. This happens well before it opens the interpreter. If that open fails the flag stays set on the bprm. binfmt_misc is at the head of the format list so an interpreter open failure that returns -ENOEXEC lets the search fall through to a later format. This means it runs the matched binary directly having never staged an interpreter. So bprm->executable is NULL while have_execfd falsely claims a descriptor is present. Consequently, begin_new_exec() dereferences the missing executable: would_dump(bprm, bprm->executable); and NULL derefs. Had it not, the hand-off later in the same function would have failed anyway. FD_ADD(0, bprm->executable) rejects a NULL file with -ENOMEM. Both sites are past the point of no return so the exec cannot be unwound either way. This can be reached by unprivileged users as binfmt_misc can be mounted in user namespaces. So a user can register an 'O' entry whose interpreter lives on a FUSE mount, have the FUSE server fail the open with -ENOEXEC and execute a native ELF file that matches the entry. have_execfd only means anything alongside the executable it describes which is not set until the interpreter has been opened and staged. So lets raise it there, next to execfd_creds, which is already set at that point. An open failure now leaves it clear, so the fallback format derives credentials from the binary and emits no AT_EXECFD, as it would for any native exec. The argv rewrite load_misc_binary() performs before the open is still not undone. This means the binary sees the interpreter path in argv[0] and its own path in argv[1] but that predates this change and only became observable once the exec stopped faulting.

Published Aug 10, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

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

0.22%

ahead of 12% of scored CVEs · Oct 30, 2026

Affects

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.

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

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < a8e9e9450df44e9dd529ec5beff283f48f4f4b97≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < a261dc49d99681c9c71f38d16e31812dc3e30412≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < 40c09b7a1d4e0a4866042c87c2bd911bb57566c8≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < 0f19d54e2524f0bf183b82f365ae4e49b4a2f788≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < 2dd0298905e97795a9c5ec30cf5b41975f821632≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < 1cd4e9b7967dab48c9f79a00b06ffff7208c0993≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < 5ccc99d58f94fad258c9c375715b3974e48620e8≥ bc2bf338d54b7aadaed49bb45b9e10d4592b2a46 and < bbf5f639918dc011aaf60aab8480218758ee68c5 and 1 more version 5.8	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 30, 2026 · 15 reading(s) · max 0.22%

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 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 10, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/40c09b7a1d4e0a4866042c87c2bd911bb57566c8
NIST National Vulnerability Database
git.kernel.org/stable/c/0f19d54e2524f0bf183b82f365ae4e49b4a2f788
NIST National Vulnerability Database
git.kernel.org/stable/c/a261dc49d99681c9c71f38d16e31812dc3e30412
NIST National Vulnerability Database
git.kernel.org/stable/c/a8e9e9450df44e9dd529ec5beff283f48f4f4b97
NIST National Vulnerability Database
git.kernel.org/stable/c/5ccc99d58f94fad258c9c375715b3974e48620e8
NIST National Vulnerability Database
git.kernel.org/stable/c/1cd4e9b7967dab48c9f79a00b06ffff7208c0993
NIST National Vulnerability Database
git.kernel.org/stable/c/2dd0298905e97795a9c5ec30cf5b41975f821632
NIST National Vulnerability Database
git.kernel.org/stable/c/bbf5f639918dc011aaf60aab8480218758ee68c5
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 3d
Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 3d
Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 3d
Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 3d
Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 3d
Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 3d

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-2026-68186 is "binfmt_misc: set have_execfd only once the interpreter is opened", 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 0.22% 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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