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CVE-2026-74476 (GCVE-0-2026-74476)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:27 – Updated: 2026-08-23 12:47
VLAI
Title
veth: convert frag_list skbs before running XDP
Summary
In the Linux kernel, the following vulnerability has been resolved: veth: convert frag_list skbs before running XDP A frag_list skb can reach veth with data_len set but nr_frags zero. veth_convert_skb_to_xdp_buff() only converts skbs that are shared, locked, have frags[], or do not have enough headroom. It later uses skb_is_nonlinear() to decide whether to set XDP_FLAGS_HAS_FRAGS and xdp_frags_size. That exposes frag_list data to XDP as if it were stored in frags[], but frags[] is empty. AF_XDP copy mode can then trust the bogus XDP fragment metadata, walk an empty fragment entry, and crash in memcpy() from __xsk_rcv(). Route non-linear skbs through skb_pp_cow_data() before exposing them to XDP, and only advertise XDP frags when the resulting skb has frags[]. skb_copy_bits() already handles frag_list input, and skb_pp_cow_data() builds frags[] output with skb_add_rx_frag(), which is the representation XDP multi-buffer expects.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < 0be3632597b8349d43a7dc4244b492dc62a05998 (git)
Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < 04958dba44dc795dc79ce2fcbc117821bbbd6542 (git)
Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < 5c1c15c540fc45820ce3033c319151ec891bc10a (git)
Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < b24ba0bbffe3e23eb2f6838881c1fabcb29fb9fb (git)
Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < f9c1fff857e93be709c8b52ed1a643f37bd82c66 (git)
Affected: 718a18a0c8a67f97781e40bdef7cdd055c430996 , < d0d6415963040c401e7a7e4e482a698ba52448cb (git)
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Linux Linux Affected: 5.18
Unaffected: 0 , < 5.18 (semver)
Unaffected: 6.1.184 , ≤ 6.1.* (semver)
Unaffected: 6.6.153 , ≤ 6.6.* (semver)
Unaffected: 6.12.103 , ≤ 6.12.* (semver)
Unaffected: 6.18.44 , ≤ 6.18.* (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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      "cve": "CVE-2026-74476",
      "id": "CVE-2026-74476",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "76",
      "product_status:under_investigation": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: veth: convert frag_list skbs before running XDP",
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      "current_release_date": "2026-08-22T00:53:15Z",
      "cve": "CVE-2026-74476",
      "id": "CVE-2026-74476",
      "initial_release_date": "2026-08-15T23:52:11Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74476",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-74476.json",
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.