CVE-2026-93138: bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux
Noroxi assessment
Priority: Monitor (action score 31/100)
- 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: 0.17% (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 2892f3f44bf865c8fb6b6c0960edec4cc91806ee, 86d11c594d60b255b526fa5260f669463fb1a063, 92863e678070f57c17c868e4bfa2441a5c61ad2b.
Low priority for now. Upgrade to Linux Linux 2892f3f44bf865c8fb6b6c0960edec4cc91806ee, 86d11c594d60b255b526fa5260f669463fb1a063, 92863e678070f57c17c868e4bfa2441a5c61ad2b 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: bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux bpf_get_btf_vmlinux() lazily parses the vmlinux BTF under the bpf_verifier_lock, but publishes the result through a plain store and re-checks it through a plain lockless load. Nothing orders the stores initializing the struct btf inside btf_parse_vmlinux() against the store publishing the pointer: On a weakly ordered arch, a concurrent first-time caller taking the lockless fast path could in principle observe the pointer before the parsed contents are visible. The mutex_unlock() does not help such a reader given it only synchronizes with a later acquisition of the same lock. Thus, publish the pointer with smp_store_release() and read it on the fast path with smp_load_acquire(). Acquire semantics are needed rather than a dependency-ordered READ_ONCE(): btf_parse_vmlinux() also populates globals outside the returned object (e.g. bpf_ctx_convert.t). An address dependency would only order accesses performed through the pointer and not cover other globals.
- Published
- Sep 17, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.1% · 7th percentile
- CWE
- —
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 7.8
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
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
If any of these changes, we'll tell you in the daily email digest.
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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.
We use this product, ask for helpAffected 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.
—
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
- 5.5affected
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before f32a4a40bc635be25d6816da4bd91e9e58c31bf3affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before a7fe72d780122eb934536f1719abad445f6afdf7affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before 978524ecfc1c539282df5858de1eec20748c6f74affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before eaf302628a78806f66d8224d6ba03fb4d5025de4affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before 2892f3f44bf865c8fb6b6c0960edec4cc91806eeaffected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before 86d11c594d60b255b526fa5260f669463fb1a063affected · git
- 8580ac9404f6240668a026785d7d8856f0530409 and later · before 92863e678070f57c17c868e4bfa2441a5c61ad2baffected · git
- before 5.5not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.190-1 | 6.1.190-1 |
| Debian:12 | linux-6.12 | before 6.12.111-1~deb12u1 | 6.12.111-1~deb12u1 |
| Debian:13 | linux | before 6.12.111-1 | 6.12.111-1 |
| Debian:14 | linux | before 7.2.6-1 | 7.2.6-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation40Plan
- CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment40Plan
- CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()40Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-93136Sep 17, 2026 · bus: mhi: ep: Fix device refcount leak in the error path of MHI device creation0Monitor
- ← EarlierCVE-2026-93137Sep 17, 2026 · bpf: Fix use-after-free on mm_struct in bpf_find_vma()31Monitor
- Later →CVE-2026-93139Sep 17, 2026 · drm/amdgpu/mes: Fix hung_queue_db_array loop limit for multi-XCC0Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 2892f3f44bf865c8fb6b6c0960edec4cc91806ee | Vendor (CNA) |
| Linux Linux | 86d11c594d60b255b526fa5260f669463fb1a063 | Vendor (CNA) |
| Linux Linux | 92863e678070f57c17c868e4bfa2441a5c61ad2b | Vendor (CNA) |
| Linux Linux | 978524ecfc1c539282df5858de1eec20748c6f74 | Vendor (CNA) |
| Linux Linux | a7fe72d780122eb934536f1719abad445f6afdf7 | Vendor (CNA) |
| Linux Linux | e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053 | Vendor (CNA) |
| Linux Linux | eaf302628a78806f66d8224d6ba03fb4d5025de4 | Vendor (CNA) |
| Linux Linux | f32a4a40bc635be25d6816da4bd91e9e58c31bf3 | Vendor (CNA) |
| debian:linux | 6.1.190-1 · Debian:12 | Package registry (OSV) |
| debian:linux | 6.12.111-1 · Debian:13 | Package registry (OSV) |
| debian:linux-6.12 | 6.12.111-1~deb12u1 · Debian:12 | Package 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.
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 researchersFinders, 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.
No nightly-computed relations.
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).
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
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- git.kernel.org/stable/c/86d11c594d60b255b526fa5260f669463fb1a063
- git.kernel.org/stable/c/92863e678070f57c17c868e4bfa2441a5c61ad2b
- git.kernel.org/stable/c/978524ecfc1c539282df5858de1eec20748c6f74
- git.kernel.org/stable/c/a7fe72d780122eb934536f1719abad445f6afdf7
- git.kernel.org/stable/c/e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053
- git.kernel.org/stable/c/eaf302628a78806f66d8224d6ba03fb4d5025de4
- git.kernel.org/stable/c/f32a4a40bc635be25d6816da4bd91e9e58c31bf3
Vendor advisories and official records. Exploit/PoC links are deliberately left out.