CVE-2026-72333

Unknown

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix tx ident leak for commands without a response Commit 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident") changed ident allocation to use an IDA, releasing idents in l2cap_put_ident() when the matching response command is received. But identifiers allocated for commands that have no response defined are never released. In particular L2CAP_LE_CREDITS is sent repeatedly for the lifetime of an LE CoC channel, so a peer streaming data to the host exhausts the 1-255 ident range after 254 credit packets. From then on l2cap_get_ident() fails: kernel: Bluetooth: Unable to allocate ident: -28 and every subsequent L2CAP_LE_CREDITS packet is sent with ident 0, which is invalid (Core Spec, Vol 3, Part A, Section 4: "Signaling identifier 0x00 is an invalid identifier and shall never be used in any command"). Remote stacks that validate the ident drop these commands, never receive new credits, and the channel stalls permanently. With default socket buffers this happens after roughly 0.5 MB of received data (the exact amount depends on the socket receive buffer): < ACL Data TX: Handle 2048 flags 0x00 dlen 12 LE L2CAP: LE Flow Control Credit (0x16) ident 0 len 4 Source CID: 64 Credits: 1 Release the ident immediately after sending L2CAP_LE_CREDITS since no response will ever release it. Use a local variable instead of chan->ident so that an ident that an EXT_FLOWCTL channel may be waiting on (e.g. a pending reconfigure) is not overwritten by a credit packet. Also add the missing L2CAP_LE_CONN_RSP case to l2cap_put_ident() so idents allocated for outgoing L2CAP_LE_CONN_REQ commands are released when the response arrives.

SeverityUnknown
CVSS—
Exploit probability—
ProductLinux
PublishedAug 15, 2026
First seenAug 15, 2026

How to fix

Update
  • Linux Linuxb8a32a5fc915b024c60f18d51b6cffd2bd64d4a6, bd1e01170341291292fd4c46b5f6949da282ca6c, 0c602cb8f148a36bfb39c25ade400bdadc023c4f, d0a2b0c81f112540a337cde1c20251bf05ddf1da, 6e1930ece855a4c256f1c7e6632d634cfb9888b5, 6.18.40, 5.11, 5.16, 6.20 or later

Affected products

ProductAffected versionsFixed in
Linux Linuxe86554c37d3d2b4b24608e0313f882cae28b8adb ≤ v < b8a32a5fc915b024c60f18d51b6cffd2bd64d4a6, 9b24ad4787cad46a3917620799f8455c6533b8df ≤ v < bd1e01170341291292fd4c46b5f6949da282ca6c, ea6cf86167b3972caa68972d2a1ad43ecbbb8331 ≤ v < 0c602cb8f148a36bfb39c25ade400bdadc023c4f, 6c3ea155e5ee3e56606233acde8309afda66d483 ≤ v < d0a2b0c81f112540a337cde1c20251bf05ddf1da, 6c3ea155e5ee3e56606233acde8309afda66d483 ≤ v < 6e1930ece855a4c256f1c7e6632d634cfb9888b5, ed97bb2cf96684ee646be6f37e4c4835f9d30caa, 84bc3197f7d87c5b89c156e853d0561a9154eceb, 8c1cdbc1bacc0cf9c27c3ebda11a81c3dcd01630, 6.18.21 ≤ v < 6.18.40, 5.10.261 ≤ v < 5.11, 5.15.212 ≤ v < 5.16, 6.19.11 ≤ v < 6.20, 7.0b8a32a5fc915b024c60f18d51b6cffd2bd64d4a6, bd1e01170341291292fd4c46b5f6949da282ca6c, 0c602cb8f148a36bfb39c25ade400bdadc023c4f, d0a2b0c81f112540a337cde1c20251bf05ddf1da, 6e1930ece855a4c256f1c7e6632d634cfb9888b5, 6.18.40, 5.11, 5.16, 6.20

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.