EchelonGraph verdictMonitorNo release containing the referenced fix is confirmed: check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule (the SSVC decision on this page).
- •Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.1%CVSS: 6.5Exploit: None knownExposed services: Not assessed
A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).
The Bluetooth Link Layer Control Procedure (LLCP) implementation for Connected Isochronous Stream (CIS) creation retains an RX node (ctx->node_ref.rx, marked NODE_RX_TYPE_RETAIN) so it can later be reused as the host notification — on the peripheral while awaiting the Host's reply to an LL_CIS_REQ, and on the central for the whole duration of a locally initiated CIS Create. In subsys/bluetooth/controller/ll_sw/ull_llcp_cc.c, the "invalid PDU received" paths of llcp_rp_cc_rx() and llcp_lp_cc_rx() terminated the connection and completed the procedure without releasing that retained node, breaking the invariant checked in llcp_lr_check_done() and llcp_rr_check_done() and orphaning the node's memory.
A peer device within radio range can reach this with a single extra LL Control PDU on an unauthenticated, unencrypted ACL link. Against a peripheral, the attacker sends a valid LL_CIS_REQ and then, before the Host replies, any unrelated LL Control PDU (for example LL_VERSION_IND), which ull_cp_rx() routes into the active remote procedure. Against a central performing a CIS Create, a malicious peripheral answers with LL_UNKNOWN_RSP for CIS_REQ, which is dispatched into the active local procedure. No pairing, encryption or user interaction is required; the code is compiled in when CONFIG_BT_CTLR_PERIPHERAL_ISO or CONFIG_BT_CTLR_CENTRAL_ISO is enabled.
In default builds (CONFIG_BT_CTLR_ASSERT_DEBUG is default y) the retained-node assertion fires immediately, producing a controller fatal error and, typically, a system reset from one injected PDU. With the development assertions disabled, each attempt permanently loses one node from the controller's small LL notification pool (LL_PDU_RX_CNT, 2 * CONFIG_BT_CTLR_LLCP_CONN) together with its memq_link_t; repeating the connect-attack-reconnect cycle exhausts the pool, after which notification allocation always fails, RX flow control stalls, and the non-disableable LL_ASSERT_ERR() in llcp_lp_cc_flush() faults. The impact is limited to availability — the leaked node is orphaned, never reused or double-freed — and recovery requires a reboot.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (6.5): severity, escalated by confirmed exploitation. This CVE's 6.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 6.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
- EG Likelihood
- 0.1% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it