Kernel-level networking bug (mlx5e) with CVSS 9.8 affects Linux servers/cloud using Mellanox NICs; can disrupt infrastructure and is broadly relevant to IT/infra teams.
CVE-2026-99079
Linux mlx5e AF_XDP bug causes double-free/data corruption in XDP refill path
Is CVE-2026-99079 being exploited?
Not confirmed. CVE-2026-99079 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.46% probability of exploitation in the next 30 days.
How severe is CVE-2026-99079?
CVE-2026-99079 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-99079?
Yes. A fix has been recorded for CVE-2026-99079. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-99079 affect?
CVE-2026-99079 affects Linux kernel (mlx5e driver), Servers using Mellanox/ConnectX NICs, Systems using AF_XDP/XDP with legacy cyclic RQ, Cloud hosts and appliances with affected kernels. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-99079?
Install vendor/upstream kernel updates with mlx5e fixes and reboot affected hosts.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Triggerable via XDP->AF_XDP RX path: kernel memory corruption/double-free leading to DoS (kernel crash) and possible local privilege escalation or arbitrary code execution.
Immediate action required
- affected>= 3f93f82988bc6b4104314bf9aa485d47fbb7e241 and < 32bbb870078d467479965c21bbc4960c57eea208
- affected>= 3f93f82988bc6b4104314bf9aa485d47fbb7e241 and < 34d1db2b18e1c1d189e34dd51923e031815f88e3
- affected>= 3f93f82988bc6b4104314bf9aa485d47fbb7e241 and < 639522e5056cade578a324acfa993ec6c9f7f5dc
- affected>= 3f93f82988bc6b4104314bf9aa485d47fbb7e241 and < 655f47477054d19de3b138840be229a1a4490d0c
- affected>= 3f93f82988bc6b4104314bf9aa485d47fbb7e241 and < e01620844c5c88b6fcf819d171df8e3976a0e76f
- affected6.4
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.