Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- Partial Red Hat: 7 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop rfcomm_apply_pn() accepts the MTU value from a remote PN (Parameter Negotiation) frame without checking for zero. When the remote peer sends an MTU of zero, d->mtu is set to 0. This causes the sendmsg path to enter an infinite loop when fragmenting data, as each fragment has size == min_t(size_t, len, 0) == 0, so the remaining length never decreases. The infinite allocation of zero-length skbs exhausts all system memory. Fix by clamping d->mtu to RFCOMM_DEFAULT_MTU when the negotiated value is zero, consistent with the initial value assigned in rfcomm_dlc_alloc().
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.12 and later | 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.12 and later Fixed in 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3 Patch available CNA
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-90088
- 2026-10-03 Alias added: GHSA-j6jv-mcf5-3925
- 2026-10-13 Affected versions changed · Red Hat
- 2026-10-13 CVSS score added · Red Hat
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-11-06 Affected versions changed · Red Hat
References
Other 8
- https://git.kernel.org/stable/c/e7c0aa45ae6c5a338661b23812bfcdef50bf3e96
- https://git.kernel.org/stable/c/cbc2962da99b6b89345267d3aa74b4b573340548
- https://git.kernel.org/stable/c/9b2e5f1928c99224345a9ed8c5dae5fc74964d6d
- https://git.kernel.org/stable/c/fc4851ff8dfb505e9a19efcc286712132bbd178d
- https://git.kernel.org/stable/c/f561e44261344adadf9d6a6dff31e3af9776d5c6
- https://git.kernel.org/stable/c/aeee917a4878af95f0c63e18c5f22eaf6299c7b8
- https://git.kernel.org/stable/c/3988cbb1be501dbff909a2ee024670e3c955a66d
- https://git.kernel.org/stable/c/44c98fd082eafd49d55a8a4077ff488175b2fe24
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Sources
- CVE-2026-90088 · CVE Program
- CVE-2026-90088 · NVD
- FIRST EPSS
- GHSA-j6jv-mcf5-3925 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-90088 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences