CVE-2023-54038: Bluetooth: hci_conn: return ERR_PTR instead of NULL when there is no link
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: 0.18% (FIRST EPSS).
- Fixed version: Linux Linux 357ab53c83a5322437fa434e9a9e3e0bafe6b383, 6.4, b4066eb04bb67e7ff66e5aaab0db4a753f37eaad.
Low priority for now. Upgrade to Linux Linux 357ab53c83a5322437fa434e9a9e3e0bafe6b383, 6.4, b4066eb04bb67e7ff66e5aaab0db4a753f37eaad 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: hci_conn: return ERR_PTR instead of NULL when there is no link hci_connect_sco currently returns NULL when there is no link (i.e. when hci_conn_link() returns NULL). sco_connect() expects an ERR_PTR in case of any error (see line 266 in sco.c). Thus, hcon set as NULL passes through to sco_conn_add(), which tries to get hcon->hdev, resulting in dereferencing a NULL pointer as reported by syzkaller. The same issue exists for iso_connect_cis() calling hci_connect_cis(). Thus, make hci_connect_sco() and hci_connect_cis() return ERR_PTR instead of NULL.
- Published
- Dec 24, 2025
- Updated
- Jun 17, 2026
- EPSS
- 0.1% · 7th percentile
- CWE
- —
Report tools
Action score
0
Monitor
Low priority for now.
- CVSS
- 0 / 40 · —
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
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.
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
- f72fc94a17d45be98aecfd59c39b5b24a6a342e2, 6.4affected
- 06149746e7203d5ffe2d6faf9799ee36203aa8b8 and later · before 357ab53c83a5322437fa434e9a9e3e0bafe6b383affected · git
- 06149746e7203d5ffe2d6faf9799ee36203aa8b8 and later · before b4066eb04bb67e7ff66e5aaab0db4a753f37eaadaffected · git
- 6.3.8 and later · before 6.4affected · semver
- before 6.4not affected · semver
- 6.4.7 and later · up to and including 6.4.*not affected · semver
- 6.5 and laternot affected · original_commit_for_fix
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:13 | linux | before 6.4.11-1 | 6.4.11-1 |
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-2023-54036Dec 24, 2025 · wifi: rtl8xxxu: Fix memory leaks with RTL8723BU, RTL8192EU0Monitor
- ← EarlierCVE-2023-54037Dec 24, 2025 · ice: prevent NULL pointer deref during reload0Monitor
- Later →CVE-2023-54039Dec 24, 2025 · can: j1939: j1939_tp_tx_dat_new(): fix out-of-bounds memory access0Monitor
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 | 357ab53c83a5322437fa434e9a9e3e0bafe6b383 | Vendor (CNA) |
| Linux Linux | 6.4 | Vendor (CNA) |
| Linux Linux | b4066eb04bb67e7ff66e5aaab0db4a753f37eaad | Vendor (CNA) |
| debian:linux | 6.4.11-1 · Debian:13 | 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.
No history yet (it accumulates with the daily EPSS job).
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✗ → ✓
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References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.