CVE-2026-90257 — Bluetooth: virtio_bt: avoid OOB read of build info string
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: virtio_bt: avoid OOB read of build info string The virtbt_setup_zephyr() sends the Zephyr vendor command 0xfc08 (Read Build Information) and hands the response to bt_dev_info() and hci_set_fw_info() as a "%s" string starting at skb->data + 1, without checking the length. A backend that answers with status only leaves that pointer past the end of the received data, so the walk reads adjacent slab memory until it meets a NUL. Those bytes reach the kernel log and the firmware-info debugfs file. To fix this, print the string with a bounded "%.*s" limited to skb->len - 1. A short or unterminated response then prints as much as arrived instead of failing setup. This mirrors commit dd068ef04412 ("Bluetooth: bpa10x: avoid OOB read of revision string in bpa10x_setup()"), which fixed the identical pattern.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
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.
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 | ≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < fb445b3466a8d1c7a0b0d0676fb475e3ce22d94e≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < d08c99abf06133a7829d46627e77e3315ca974d2≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < 0e388d805233a883a31271676eae6031dfc9e898≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < 54e9387eb7546eaa6f600220599d55740956ffc3≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < be1e3df2c49c91b0a052c6563884e8d39bd768b2≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < 84ea9c99874804f5ca13f35bbc186ba93902f30f≥ afd2daa26c7abd734d78bd274fc6c59a15e61063 and < 502adc06ba76dee19c292ae4a07d74d202fe734dversion 5.13 | Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 18, 2026 · 3 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.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× References added · Oct 19, 2026 – Oct 19, 2026
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
9 on the record
- git.kernel.org/stable/c/d08c99abf06133a7829d46627e77e3315ca974d2
- nvd.nist.gov/vuln/detail/CVE-2026-90257
- github.com/advisories/GHSA-jc9v-mfxc-m9mm
- git.kernel.org/stable/c/be1e3df2c49c91b0a052c6563884e8d39bd768b2
- git.kernel.org/stable/c/54e9387eb7546eaa6f600220599d55740956ffc3
- git.kernel.org/stable/c/fb445b3466a8d1c7a0b0d0676fb475e3ce22d94e
- git.kernel.org/stable/c/0e388d805233a883a31271676eae6031dfc9e898
- git.kernel.org/stable/c/502adc06ba76dee19c292ae4a07d74d202fe734d
- git.kernel.org/stable/c/84ea9c99874804f5ca13f35bbc186ba93902f30f
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 1d
- Unknown CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 1d
- Unknown CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 1d
- Unknown CVE-2026-98865 sched_ext: Don't run ops.dequeue() with a DSQ lock held 1d
- Unknown CVE-2026-98864 sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task 1d
- Unknown CVE-2026-98863 KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails 1d
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-2026-90257 is "Bluetooth: virtio_bt: avoid OOB read of build info string", 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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