Vulnerabilities

CVE-2026-53362 is an out-of-bounds write (CWE-787) in the Linux kernel's IPv6 output path: __ip6_append_data() mis-accounts fraggap bytes on the paged-allocation branch, leaving the new skb's linear area undersized so the copy of carried-over fragment-gap data spills past skb->end into the trailing skb_shared_info. An unprivileged local user can trigger the corruption by sending over a UDPv6 socket using MSG_MORE combined with MSG_SPLICE_PAGES; the bad accounting was introduced by commit 773ba4fe9104 ('ipv6: avoid partial copy for zc') and became triggerable when commit ce650a166335 allowed the MSG_SPLICE_PAGES case to proceed instead of returning -EINVAL. Successful triggering causes kernel memory corruption that, per the high confidentiality/integrity/availability scores, can lead to loss of data confidentiality, integrity and availability — potentially local privilege escalation or a system crash. Any Linux system running a kernel with the affected code is exposed; the source data provides no specific affected version numbers, only the introducing and trigger commits. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2026-08-27, indicating known in-the-wild exploitation (ransomware use unknown), with EPSS at 0.5% and no public PoC known.

Do: Apply the kernel fix per vendor instructions: upgrade to Linux kernel builds containing the fraggap-accounting resolution for __ip6_append_data(), following CISA's BOD 26-04 patching requirements (for cloud services, follow BOD guidance or discontinue use if mitigations are unavailable); no fixed version numbers were provided in the source data, so confirm with your distribution/vendor that the fix commit is included. Until patched, prioritize multi-user hosts and systems where untrusted local users can open UDPv6 sockets, since exploitation requires local unprivileged access with MSG_MORE and MSG_SPLICE_PAGES. Track KEV-required remediation deadlines, as the flaw is cataloged as exploited in the wild (added 2026-08-27).

CVE-2022-0995 is an out-of-bounds (OOB) memory write in the Linux kernel's watch_queue event notification subsystem (CWE-787) that can overwrite parts of kernel state. A local user can trigger it through the watch_queue interface, for example by supplying a crafted event filter definition, causing the kernel to write beyond allocated memory when event notifications are processed. Successful exploitation may allow the local user to gain privileged (kernel/root) access or crash the system, yielding high impact on confidentiality, integrity, and availability (CVSS 3.1: 7.8, local attack vector). Affected systems include mainstream Linux kernels (Fedora is explicitly listed) and NetApp HCI appliance firmware products that ship the affected kernel. The flaw is confirmed exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2026-08-26, two public proof-of-concepts are available, and EPSS puts 30-day exploitation probability at 9.5% (95th percentile), though ransomware use is unconfirmed.

Do: Apply updated kernels from your distribution or vendor (Fedora kernel updates; NetApp fixes are delivered via the HCI firmware updates in its security advisory) and prioritize internet-exposed, multi-user hosts per CISA BOD 26-04, including the required forensics triage checks. Because exploitation requires local access, restrict untrusted local code execution and shell access on unpatched systems, and hunt for signs of local privilege escalation on high-exposure hosts. After remediation, verify the patched kernel package is installed and that the running kernel has actually been booted into the fixed version.