CVE-2026-43500

Published May 11, 2026

Last updated 4 hours ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE handler in rxrpc_verify_response() copy the skb to a linear one before calling into the security ops only when skb_cloned() is true. An skb that is not cloned but still carries externally-owned paged fragments (e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via __ip_append_data, or a chained skb_has_frag_list()) falls through to the in-place decryption path, which binds the frag pages directly into the AEAD/skcipher SGL via skb_to_sgvec(). Extend the gate to also unshare when skb_has_frag_list() or skb_has_shared_frag() is true. This catches the splice-loopback vector and other externally-shared frag sources while preserving the zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC page_pool RX, GRO). The OOM/trace handling already in place is reused.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-787

Social media

Hype score
Not currently trending

  1. Critical Linux privilege escalation "Dirty Frag" (CVE-2026-43284, CVE-2026-43500) exploits IPsec ESP and RxRPC in-place decryption to corrupt page cache. Zero-day PoC public, patches pending. Technical details: • Affects Linux 4.10-7.0 via ESP (2017 commit) and RxRPC (2023) ht

    @DFIR_Radar

    8 May 2026

    236 Impressions

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Configurations

Related CVEs

  1. In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: avoid in-place decrypt on shared skb frags MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(), so later paths that may modify packet data can first make a private copy. The IPv4/IPv6 datagram append paths did not set this flag when splicing pages into UDP skbs. That leaves an ESP-in-UDP packet made from shared pipe pages looking like an ordinary uncloned nonlinear skb. ESP input then takes the no-COW fast path for uncloned skbs without a frag_list and decrypts in place over data that is not owned privately by the skb. Mark IPv4/IPv6 datagram splice frags with SKBFL_SHARED_FRAG, matching TCP. Also make ESP input fall back to skb_cow_data() when the flag is present, so ESP does not decrypt externally backed frags in place. Private nonlinear skb frags still use the existing fast path. This intentionally does not change ESP output. In esp_output_head(), the path that appends the ESP trailer to existing skb tailroom without calling skb_cow_data() is not reachable for nonlinear skbs: skb_tailroom() returns zero when skb->data_len is nonzero, while ESP tailen is positive. Thus ESP output will either use the separate destination-frag path or fall back to skb_cow_data().•CVE-2026-43284
  2. In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ec_bhf: Fix dma_free_coherent() dma handle dma_free_coherent() in error path takes priv->rx_buf.alloc_len as the dma handle. This would lead to improper unmapping of the buffer. Change the dma handle to priv->rx_buf.alloc_phys.•CVE-2026-43283
  3. In the Linux kernel, the following vulnerability has been resolved: RDMA/ionic: Fix potential NULL pointer dereference in ionic_query_port The function ionic_query_port() calls ib_device_get_netdev() without checking the return value which could lead to NULL pointer dereference, Fix it by checking the return value and return -ENODEV if the 'ndev' is NULL.•CVE-2026-43282
  4. In the Linux kernel, the following vulnerability has been resolved: mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate() Although it is guided that `#mbox-cells` must be at least 1, there are many instances of `#mbox-cells = <0>;` in the device tree. If that is the case and the corresponding mailbox controller does not provide `fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will be used by default and out-of-bounds accesses could occur due to lack of bounds check in that function.•CVE-2026-43281
  5. In the Linux kernel, the following vulnerability has been resolved: drm/xe: Add bounds check on pat_index to prevent OOB kernel read in madvise When user provides a bogus pat_index value through the madvise IOCTL, the xe_pat_index_get_coh_mode() function performs an array access without validating bounds. This allows a malicious user to trigger an out-of-bounds kernel read from the xe->pat.table array. The vulnerability exists because the validation in madvise_args_are_sane() directly calls xe_pat_index_get_coh_mode(xe, args->pat_index.val) without first checking if pat_index is within [0, xe->pat.n_entries). Although xe_pat_index_get_coh_mode() has a WARN_ON to catch this in debug builds, it still performs the unsafe array access in production kernels. v2(Matthew Auld) - Using array_index_nospec() to mitigate spectre attacks when the value is used v3(Matthew Auld) - Put the declarations at the start of the block (cherry picked from commit 944a3329b05510d55c69c2ef455136e2fc02de29)•CVE-2026-43280

References

Sources include official advisories and independent security research.