CVE-2026-74740: net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain
CSIRTS triage
- What
- Time-of-check-time-of-use race condition causing null pointer dereference in netlink traffic control act_api.
- Who is affected
- Linux systems using netlink-based traffic control API.
- Urgency
- Medium severity (CVSS 4.1); denial of service only, requires local network namespace access.
- Action
- Apply kernel patch for net/sched act_api TOCTOU fix.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-74740
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-747400.18% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 7% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-74740 | coverage & exploitation status | NVD · CVE.org |
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