In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop
l2cap_config_req() processes CONFIG_REQ for channels in BT_CONNECTED
state to support L2CAP reconfiguration (e.g. MTU changes). However,
since both CONF_INPUT_DONE and CONF_OUTPUT_DONE are already set from
the initial configuration, the reconfiguration path falls through to
l2cap_ertm_init(), which re-initializes tx_q, srej_q, srej_list, and
retrans_list without freeing the previous allocations and sets
chan->sdu to NULL without freeing the existing skb. This leaks all
previously allocated ERTM resources.
Additionally, l2cap_parse_conf_req() does not validate the minimum
value of remote_mps derived from the RFC max_pdu_size option. A zero
value propagates to l2cap_segment_sdu() where pdu_len becomes zero,
causing the while loop to never terminate since len is never
decremented, exhausting all available memory.
Fix the double-init by skipping l2cap_ertm_init() and
l2cap_chan_ready() when the channel is already in BT_CONNECTED state,
while still allowing the reconfiguration parameters to be updated
through l2cap_parse_conf_req(). Also add a pdu_len zero check in
l2cap_segment_sdu() as a safeguard.
References
Configurations
Configuration 1 (hide)
|
History
28 Apr 2026, 14:41
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| First Time |
Linux
Linux linux Kernel |
|
| CWE | CWE-835 | |
| References | () https://git.kernel.org/stable/c/042e2cd4bb11e5313b19b87593616524949e4c52 - Patch | |
| References | () https://git.kernel.org/stable/c/25f420a0d4cfd61d3d23ec4b9c56d9f443d91377 - Patch | |
| References | () https://git.kernel.org/stable/c/52667c859fe33f70c2e711cb81bbd505d5eb8e75 - Patch | |
| References | () https://git.kernel.org/stable/c/900e4db5385ec2cacd372345a80ab9c8e105b3a3 - Patch | |
| References | () https://git.kernel.org/stable/c/9760b83cfd24b38caee663f429011a0dd6064fa9 - Patch | |
| References | () https://git.kernel.org/stable/c/9a21a631ee034b1573dce14b572a24943dbfd7ae - Patch | |
| References | () https://git.kernel.org/stable/c/de37e2655b7abc3f59254c6b72256840f39fc6d5 - Patch | |
| References | () https://git.kernel.org/stable/c/e7aab23b7df89a3d754a5f0a7d2237548b328bd0 - Patch | |
| CPE | cpe:2.3:o:linux:linux_kernel:5.7:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* |
22 Apr 2026, 14:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-22 14:16
Updated : 2026-04-28 14:41
NVD link : CVE-2026-31498
Mitre link : CVE-2026-31498
CVE.ORG link : CVE-2026-31498
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-835
Loop with Unreachable Exit Condition ('Infinite Loop')