CVE-2026-74752
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk36th percentile - higher than 36% of all known CVEs
Summary
In the Linux kernel's SCTP protocol, the COOKIE_ECHO state restoration does not properly validate AUTH fields (RANDOM, HMACS, CHUNKS) originating from peer-controlled cookie bytes. Forged lengths or identifiers can lead to out-of-bounds reads and even a write past a buffer, potentially enabling local privilege escalation.
Risk Assessment
A local attacker could exploit this vulnerability to escalate privileges or cause a system crash. Lack of cookie parameter validation may lead to kernel memory corruption.
Recommendation
Apply a Linux kernel update that includes the fix validating RANDOM, HMACS, and CHUNKS parameters at the cookie trust boundary before copying them into the association.
Other vulnerabilities in Linux kernel
See all- CVE-2026-98374Unknown
In the Linux kernel, a use-after-free vulnerability exists in tcp_send_synack() involving retransmit_skb_hint. When tcp_send_synack() replaces the cloned SYN skb at the head of the retransmit queue with a copy, it frees the original but tp->retransmit_skb_hint still points to the freed object, which can be exploited by an unprivileged TFO client to trigger a use-after-free.
- CVE-2026-98373Unknown
In the Linux kernel, a bug exists in move_hugetlb_page_tables() where the destination address is advanced too far when the source and destination offsets within their page tables differ. This can lead to a kernel panic on x86-64.
- CVE-2026-98048Unknown
In the Linux kernel's BPF subsystem, mark_fastcall_pattern_for_call() must ensure that a matched "spill; call; fill" instruction series is not interrupted by a jump. Otherwise the rewrite applied by bpf_remove_fastcall_spills_fills() is unsound. The fix records instructions targeted by jumps in insn_aux_data[*].jump_target and uses this flag to stop growing a pattern.
- CVE-2026-98047Unknown
In the Linux kernel's BPF subsystem, in_rbtree_lock_required_cb() only checks the innermost verifier frame, so rbtree callback restrictions disappear in a nested static subprogram call frame. The subprogram can unlock the tree, remove and drop the node being compared, then relock, leading to freed memory being linked into the tree.
- CVE-2026-98045Unknown
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- CVE-2026-98044Unknown
In the Linux kernel, the BPF verifier mishandled legacy packet-load instructions (BPF_LD_ABS/BPF_LD_IND) reached from callbacks, triggering a verifier bug warning and an -EFAULT on BPF_PROG_LOAD. A privileged program loader could trigger this issue.
- CVE-2026-98043Unknown
In the Linux kernel, the BPF verifier incorrectly inferred that a pointer with an unbounded offset is non-NULL based solely on its type. As a result, a BPF program could pass verification while a NULL pointer dereference occurred at runtime.
- CVE-2026-98042Unknown
In the Linux kernel, the BPF verifier could resurrect a scalar id dropped by collect_linked_regs() because snapshots of compared registers were taken before linked registers were collected. This could lead to range inconsistencies and precision propagation issues.
- CVE-2026-98041High
In the Linux kernel, the BPF verifier incorrectly predicted the outcome of pointer vs zero comparisons in JMP32 instructions, failing to distinguish BPF_JMP from BPF_JMP32 comparisons. This led to incorrect inference that a jump is always taken.
- CVE-2026-98040Unknown
In the Linux kernel, the BPF verifier did not mark the zero register as precise for a register-form NULL check. As a result, one path was pruned and the program could dereference a zero pointer at runtime.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: sctp: validate cookie AUTH state before use When cookie authentication is disabled, COOKIE_ECHO restores fixed-size AUTH fields directly from peer-controlled cookie bytes. A forged RANDOM length, HMAC list, or CHUNKS list can then reach association consumers with lengths or identifiers that were never validated against the local backing arrays. A forged RANDOM length can cause out-of-bounds reads during key-vector construction. A forged HMAC identifier also caused a 32-byte write past a zero-length AUTH chunk, providing a primitive for a local privilege escalation chain. Validate the cookie's RANDOM, HMACS, and CHUNKS parameters at the cookie trust boundary before copying them into the association. Reject invalid types, malformed lengths, unsupported HMAC identifiers, HMAC lists without SHA1, and forbidden chunk ids.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS