Answer in brief
CVE-2026-23398 records a Medium severity (CVSS 5.5) security vulnerability in CVE-2026-23398. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Vulnerability describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-23398 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Answer in brief
CVE-2026-23398 records a Medium severity (CVSS 5.5) security vulnerability in CVE-2026-23398. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Vulnerability describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-23398 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
In the Linux kernel, the following vulnerability has been resolved: icmp: fix NULL pointer dereference in icmp_tag_validation() icmp_tag_validation() unconditionally dereferences the result of rcu_dereference(inet_protos[proto]) without checking for NULL. The inet_protos[] array is sparse -- only about 15 of 256 protocol numbers have registered handlers. When ip_no_pmtu_disc is set to 3 (hardened PMTU mode) and the kernel receives an ICMP Fragmentation Needed error with a quoted inner IP header containing an unregistered protocol number, the NULL dereference causes a kernel panic in softirq context. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143) Call Trace: <IRQ> icmp_rcv (net/ipv4/icmp.c:1527) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207) ip_local_deliver_finish (net/ipv4/ip_input.c:242) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) __netif_receive_skb_one_core (net/core/dev.c:6164) process_backlog (net/core/dev.c:6628) handle_softirqs (kernel/softirq.c:561) </IRQ> Add a NULL check before accessing icmp_strict_tag_validation. If the protocol has no registered handler, return false since it cannot perform strict tag validation.
Reported by NVD (nvd).
CVE-2026-23398 records a Medium severity (CVSS 5.5) security vulnerability in CVE-2026-23398. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL GuardIn the Linux kernel, the following vulnerability has been resolved: icmp: fix NULL pointer dereference in icmp_tag_validation() icmp_tag_validation() unconditionally dereferences the result of rcu_dereference(inet_protos[proto]) without checking for NULL. The inet_protos[] array is sparse -- only about 15 of 256 protocol numbers have registered handlers. When ip_no_pmtu_disc is set to 3 (hardened PMTU mode) and the kernel receives an ICMP Fragmentation Needed error with a quoted inner IP header containing an unregistered protocol number, the NULL dereference causes a kernel panic in softirq context. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143) Call Trace: <IRQ> icmp_rcv (net/ipv4/icmp.c:1527) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207) ip_local_deliver_finish (net/ipv4/ip_input.c:242) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) __netif_receive_skb_one_core (net/core/dev.c:6164) process_backlog (net/core/dev.c:6628) handle_softirqs (kernel/softirq.c:561) </IRQ> Add a NULL check before accessing icmp_strict_tag_validation. If the protocol has no registered handler, return false since it cannot perform strict tag validation.
Reported by NVD (nvd).
CVE-2026-23398 records a Medium severity (CVSS 5.5) security vulnerability in CVE-2026-23398. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL Guard