PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-10683 zephyrproject CVE debrief

A denial-of-service vulnerability exists in the Synopsys DesignWare I2C driver operating in target/slave mode. An I2C master on the same physical bus can trigger this vulnerability, causing the I2C target function to malfunction for all subsequent write transactions. This issue arises from the rx_full interrupt handler gating the write_requested() callback on dw->state != CMD_SEND, and dw->state is only reset to READY on a STOP interrupt. The START_DET interrupt, which would reset the state on every (re)START, was never added to the enabled interrupt mask in i2c_dw_slave_register(), rendering the recovery path ineffective. As a result, if the STOP interrupt is lost or the bus master issues a legal WRITE-repeated-START-WRITE sequence with the same direction, the driver remains in CMD_SEND permanently. Users of the Synopsys DesignWare I2C driver operating in target/slave mode should be aware of this vulnerability and take steps to mitigate its impact.

Vendor
zephyrproject
Product
zephyr
CVSS
LOW 2.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-27
Original CVE updated
2026-09-01
Advisory published
2026-07-27
Advisory updated
2026-09-01

Who should care

Users of the Synopsys DesignWare I2C driver operating in target/slave mode should be aware of this vulnerability and take steps to mitigate its impact. This includes ensuring proper bus management, monitoring for potential bus glitches or resets, and applying the patch provided by the vendor.

Technical summary

The Synopsys DesignWare I2C driver operating in target/slave mode is vulnerable to a denial-of-service attack. The vulnerability is caused by the rx_full interrupt handler gating the write_requested() callback on dw->state != CMD_SEND, and dw->state is only reset to READY on a STOP interrupt. An I2C master on the same physical bus can deliberately trigger this, causing the I2C target function to malfunction for all subsequent write transactions.

Defensive priority

The target peripheral can be protected by ensuring proper bus management and monitoring for potential bus glitches or resets. Implementing compensating controls, such as reset mechanisms, can also help mitigate the impact of this vulnerability.

Recommended defensive actions

  • Implement monitoring to detect potential bus glitches or resets
  • Ensure proper bus management to prevent exploitation
  • Apply the patch provided by the vendor to unmask the START_DET interrupt
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is caused by the rx_full interrupt handler gating the write_requested() callback on dw->state != CMD_SEND, and dw->state is only reset to READY on a STOP interrupt. The START_DET interrupt, which would reset the state on every (re)START, is not enabled in the interrupt mask.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-10683 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-10683

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-10683 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-10683

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.