CVE-2026-90087: Bluetooth: do not leak an hci_conn when a second LE connect is rejected
Noroxi assessment
Priority: Monitor (action score 0/100)
- 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: 0.21% (FIRST EPSS).
- Fixed version: Linux Linux 2eafcf310f4e0ad4f387881db01116bbe3cc0b39, 42fe0278d05d75c405abad62dafaeec713cec2e2, 5.18.
Low priority for now. Upgrade to Linux Linux 2eafcf310f4e0ad4f387881db01116bbe3cc0b39, 42fe0278d05d75c405abad62dafaeec713cec2e2, 5.18 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: Bluetooth: do not leak an hci_conn when a second LE connect is rejected create_le_conn_complete() decides whether the failed connection is still pending by comparing it against hci_lookup_le_connect(), which returns the first LE connection in BT_CONNECT. That is the same connection only while at most one is pending. Two can be pending. Connections created on the passive scan path sit in BT_CONNECT with HCI_CONN_SCANNING set and are invisible to hci_lookup_le_connect() until hci_le_create_conn_sync() clears the flag when their command is issued, so the -EBUSY guard in hci_connect_le() does not prevent a second connection from being queued while the first is still on the scan path. Whenever two connections are in BT_CONNECT at once, the lookup may return one connection while create_le_conn_complete() is reporting the failure of the other; the early exit then drops the error and hci_conn_failed() never runs on the connection that failed. The controller also rejects a second HCI_OP_LE_CREATE_CONN issued while another connection creation is still outstanding, per Core Spec Vol 4, Part E. The spec calls for Command Disallowed there; the bcm43438 observed here answers with an LMP/LL error code instead, which bt_to_errno() maps to the -EPROTO (-71) in the log below. The leaked connection stays in BT_CONNECT forever, and because hci_connect_le() refuses to dial while hci_lookup_le_connect() finds anything, every subsequent attempt to reach any peer fails with -EBUSY and no command reaches the controller at all. Seen on a bcm43438 with two BLE peers polled on the same interval (state 5 is BT_CONNECT; both handles are UNSET ones, allocated from the ida above HCI_CONN_HANDLE_MAX): Bluetooth: hci1: Opcode 0x2013 failed: -71 # hcitool con < LE 14:9C:EF:03:68:81 handle 3840 state 5 lm CENTRAL < LE C4:D3:6A:8C:B5:38 handle 3841 state 5 lm CENTRAL A btmon capture across the next ten minutes of connect attempts contains no HCI_OP_LE_CREATE_CONN at all; outgoing LE connections do not recover until the adapter is reset. With this change the same scenario fails the rejected connection cleanly and further connects to both peers go through. Ask about the connection itself instead of about the device.
- Published
- Sep 17, 2026
- Updated
- Oct 30, 2026
- EPSS
- 0.2% · 11th percentile
- CWE
- —
Report tools
Action score
0
Monitor
Low priority for now.
- CVSS
- 0 / 40 · —
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
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.
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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
- ee23bb0e4315476413e4e1ed9c486d6f9472294d, da499d598cb84b45a2aa930dc9213dc9a746a81d, 5.19affected
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before 42fe0278d05d75c405abad62dafaeec713cec2e2affected · git
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before a78d16530c1538a215a827c7c3a4b408d6759bc0affected · git
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before 78970b39529844b31df2949015f66752e17210feaffected · git
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before 8a8585e421d06f878b33ef79f82cace0d485e3d8affected · git
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before 2eafcf310f4e0ad4f387881db01116bbe3cc0b39affected · git
- c9f73a2178c12fb24d2807634209559d6a836e08 and later · before 7e1e4047200fd7519f9bdfe8a001437715e618b4affected · git
- 5.17.14 and later · before 5.18affected · semver
- 5.18.3 and later · before 5.19affected · semver
- before 5.19not 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 | from 0 | — |
| 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-2026-90085Sep 17, 2026 · octeontx2-af: fix NULL deref in NIX TM tree debugfs read path0Monitor
- ← EarlierCVE-2026-90086Sep 17, 2026 · xsk: honor XDP_TX_METADATA in zero-copy path0Monitor
- Later →CVE-2026-90088Sep 17, 2026 · Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop0Monitor
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 | 2eafcf310f4e0ad4f387881db01116bbe3cc0b39 | Vendor (CNA) |
| Linux Linux | 42fe0278d05d75c405abad62dafaeec713cec2e2 | Vendor (CNA) |
| Linux Linux | 5.18 | Vendor (CNA) |
| Linux Linux | 5.19 | Vendor (CNA) |
| Linux Linux | 78970b39529844b31df2949015f66752e17210fe | Vendor (CNA) |
| Linux Linux | 7e1e4047200fd7519f9bdfe8a001437715e618b4 | Vendor (CNA) |
| Linux Linux | 8a8585e421d06f878b33ef79f82cace0d485e3d8 | Vendor (CNA) |
| Linux Linux | a78d16530c1538a215a827c7c3a4b408d6759bc0 | Vendor (CNA) |
| debian:linux | 7.2.6-1 · Debian:14 | 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.
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Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
No CVSS vector for this record, so attack conditions can't be derived.
Weakness class (CWE)
—
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 (5 more)Show less
- git.kernel.org/stable/c/42fe0278d05d75c405abad62dafaeec713cec2e2
- git.kernel.org/stable/c/78970b39529844b31df2949015f66752e17210fe
- git.kernel.org/stable/c/7e1e4047200fd7519f9bdfe8a001437715e618b4
- git.kernel.org/stable/c/8a8585e421d06f878b33ef79f82cace0d485e3d8
- git.kernel.org/stable/c/a78d16530c1538a215a827c7c3a4b408d6759bc0
Vendor advisories and official records. Exploit/PoC links are deliberately left out.