CVE-2026-53073: Bluetooth: hci_ldisc: Clear HCI_UART_PROTO_INIT on error
Vulnerability summary
CVE-2026-53073 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.11% chance of exploitation in the next 30 days, higher than 1.4% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 51 · Related 49Timeline
- 24-06-2026PublishedVulnerability first disclosed.
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_ldisc: Clear HCI_UART_PROTO_INIT on error When hci_register_dev() fails in hci_uart_register_dev() HCI_UART_PROTO_INIT is not cleared before calling hu->proto->close(hu) and setting hu->hdev to NULL. This means incoming UART data will reach the protocol-specific recv handler in hci_uart_tty_receive() after resources are freed. Clear HCI_UART_PROTO_INIT with a write lock before calling hu->proto->close() and setting hu->hdev to NULL. The write lock ensures all active readers have completed and no new reader can enter the protocol recv path before resources are freed. This allows the protocol-specific recv functions to remove the "HCI_UART_REGISTERED" guard without risking a null pointer dereference if hci_register_dev() fails.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.11%
Chance of exploitation in the next 30 days
Percentile
1%
Versus all other CVEs
30-day change
Decrease -0.05 pp
From 0.16% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu154 products
- linux< 5.15.0-186.196 | < 6.8.0-136.136 | All versions (No fix recorded) | < 7.0.0-28.28
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1112.119 | < 6.8.0-1061.64 | All versions (No fix recorded) | < 7.0.0-1009.9
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ a40f94f7caa8d3421b64f63ac31bc0f24c890f39, < ebb39b2d81731b83ee71a1ba6dd0291a57b5ac07 | ≥ 9e5a0f5777162e503400c70c6ed25fbbe2d38799, < ed4033fb85ccaaf6c3983be3c7b037e48253d232 | ≥ 80f14e9de6a43a0bd8194cad1003a3e6dcbc3984, < 356dee1bcac4d0d9152390561fa63331ebff211b | ≥ 02e1bcdfdf769974e7e9fa285e295cd9852e2a38, < a673cf6c4ac702cb79ac1f4d7fc4de763a6a3e40 | ≥ 281782d2c6730241e300d630bb9f200d831ede71, < f4b69c35813c432973d340d3600c01de106ed474 | ≥ 5df5dafc171b90d0b8d51547a82657cd5a1986c7, < 3daa5818e473ed60eb69d8b5c71b651909d28c5a | ≥ 5df5dafc171b90d0b8d51547a82657cd5a1986c7, < 194f029a4d7f739e44ebc1f473120187b4de5104 | ≥ 5df5dafc171b90d0b8d51547a82657cd5a1986c7, < 68d39ea5e0adc9ecaea1ce8abd842ec972eb8718 | 1dcf08fcff5ca529de6dc0395091f28854f4e54a | 8e5aff600539e5faea294d9612cca50220e602b8 | db7509fa110dd9b11134b75894677f30353b2c51 | ≥ 5.10.237, < 5.10.258 | ≥ 5.15.181, < 5.15.209 | ≥ 6.1.135, < 6.1.175 | ≥ 6.6.88, < 6.6.141 | ≥ 6.12.24, < 6.12.91 | ≥ 5.4.293, < 5.5 | ≥ 6.13.12, < 6.14 | ≥ 6.14.3, < 6.15 | 6.15
- linux_kernel≥ 5.4.293, < 5.5 | ≥ 5.10.237, < 5.10.258 | ≥ 5.15.181, < 5.15.209 | ≥ 6.1.135, < 6.1.175 | ≥ 6.6.88, < 6.6.141 | ≥ 6.12.24, < 6.12.91 | ≥ 6.13.12, < 6.14 | ≥ 6.14.3, < 6.18.33 | ≥ 6.19, < 7.0.10
Debian1 product
- linux< 6.1.176-1 | < 6.12.94-1 | < 7.0.10-1
3 vendors · 157 products
