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CVE-2026-74550 (GCVE-0-2026-74550)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:27 – Updated: 2026-08-19 16:38
VLAI
Title
net: do not send ICMP/NDISC Redirects when peer allocation fails
Summary
In the Linux kernel, the following vulnerability has been resolved: net: do not send ICMP/NDISC Redirects when peer allocation fails When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry under memory pressure or tree size caps, redirect handlers previously fell back to sending un-rate-limited ICMP/NDISC Redirect messages. In IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL. In IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into inet_peer_xrlim_allow(), which returned true when peer == NULL. Because ICMP/NDISC Redirects are not part of the default global rate limit mask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates an un-rate-limited ICMP packet storm. Fix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and ndisc_send_redirect() when peer is NULL.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < c0adf8b4247bcc5a145a25c1929006eb392580bb (git)
Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < f5ecaa7ea7686fa7ecdb6affc9d3a9a42e4524b1 (git)
Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < 21666f7af49a90ef44d474916b8ef4402dfd74f5 (git)
Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < 5ec5f00fc606a6df8434948c4552b3cb1176595d (git)
Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < 828f6670d110ff2bf44c743037b38badc315704c (git)
Affected: 92d8682926342d2b6aa5b2ecc02221e00e1573a0 , < dbc3791e3b2472e1ccc08947e0f83b443470ff4f (git)
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Linux Linux Affected: 2.6.39
Unaffected: 0 , < 2.6.39 (semver)
Unaffected: 6.1.183 , ≤ 6.1.* (semver)
Unaffected: 6.6.151 , ≤ 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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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-21T07:20:12+00:00",
      "cve": "CVE-2026-74550",
      "id": "CVE-2026-74550",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net: do not send ICMP/NDISC Redirects when peer allocation fails",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74550.json",
      "version": "3"
    },
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      "current_release_date": "2026-09-09T00:00:16Z",
      "cve": "CVE-2026-74550",
      "id": "CVE-2026-74550",
      "initial_release_date": "2026-08-15T23:50:29Z",
      "product_status:first_fixed": "106",
      "product_status:known_affected": "345",
      "product_status:recommended": "11",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74550",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-74550.json",
      "version": "5"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.