Answer in brief
CVE-2026-31498 records a Unknown severity vulnerability in Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=96298f640104e4cd9a913a6e50b0b981829b94ff <9760b83cfd24b38caee663f429011a0dd6064fa9 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <de37e2655b7abc3f59254c6b72256840f39fc6d5 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <e7aab23b7df89a3d754a5f0a7d2237548b328bd0 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <52667c859fe33f70c2e711cb81bbd505d5eb8e75 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <9a21a631ee034b1573dce14b572a24943dbfd7ae || >=96298f640104e4cd9a913a6e50b0b981829b94ff <900e4db5385ec2cacd372345a80ab9c8e105b3a3 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <042e2cd4bb11e5313b19b87593616524949e4c52 || >=96298f640104e4cd9a913a6e50b0b981829b94ff <25f420a0d4cfd61d3d23ec4b9c56d9f443d91377 || 4ad03ff6f680681c5f78254e37c4c856fa953629 || b7d0ca715c1008acd2fc018f02a56fed88f78b75 || 799263eb37a4f7f6d39334046929c3bc92452a7f || 8828622fb9b4201eeb0870587052e3d834cfaf61 || b432ea85ab8472763870dd0f2c186130dd36d68c || >=4.4.238 <4.5 || >=4.9.238 <4.10 || >=4.14.200 <4.15 || >=4.19.149 <4.20 || >=5.4.69 <5.5 | 9760b83cfd24b38caee663f429011a0dd6064fa9, de37e2655b7abc3f59254c6b72256840f39fc6d5, e7aab23b7df89a3d754a5f0a7d2237548b328bd0, 52667c859fe33f70c2e711cb81bbd505d5eb8e75, 9a21a631ee034b1573dce14b572a24943dbfd7ae, 900e4db5385ec2cacd372345a80ab9c8e105b3a3, 042e2cd4bb11e5313b19b87593616524949e4c52, 25f420a0d4cfd61d3d23ec4b9c56d9f443d91377, 4.5, 4.10, 4.15, 4.20, 5.5 |
| Linux/Linuxgeneric | 5.7 | Not reported |
Published upstream
Apr 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.