PatchTheCVECVE-2026-99076: In the Linux kernel, the following vulnerability has been resolved: ipv6: udp: Create exceptions before socke
CVE-2026-99076 is a high-severity flaw (CVSS n/a) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
In the Linux kernel, the following vulnerability has been resolved: ipv6: udp: Create exceptions before socket matching Currently, when ICMPv6 Packet Too Big and Redirect Message packets are locally delivered and quote a UDP packet, an exception is only created in the IPv6 exception cache if the kernel can match the UDP packet to an existing socket. This behavior allows off-path attackers to conduct a side-channel attack on the exception cache
Why this priority
- On your watchlist
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | n/a (High) |
| EPSS exploit chance | 0.2% (top 89%) |
| CISA exploited list | No |
| Published | 2026-10-23 |
| Last modified | 2026-10-23 |
Last updated 2026-10-23 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Official advisories
- Linux Kernel CVE Announce: CVE-2026-99076: ipv6: udp: Create exceptions before socket matching 2026-10-23
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-99076?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-99076 being exploited?
CVE-2026-99076 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-99076 affect?
CVE-2026-99076 affects affected software. Severity is high (CVSS n/a). In the Linux kernel, the following vulnerability has been resolved: ipv6: udp: Create exceptions before socket matching Currently, when ICMPv6 Packet Too Big and Redirect Message packets are locally delivered and quote a UDP packet, an ex
How urgent is CVE-2026-99076?
Priority 8/100. On your watchlist