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CVE-2026-43491 (GCVE-0-2026-43491)

Vulnerability from cvelistv5 – Published: 2026-05-19 10:44 – Updated: 2026-08-19 16:27
VLAI
Title
net: qrtr: ns: Limit the maximum server registration per node
Summary
In the Linux kernel, the following vulnerability has been resolved: net: qrtr: ns: Limit the maximum server registration per node Current code does no bound checking on the number of servers added per node. A malicious client can flood NEW_SERVER messages and exhaust memory. Fix this issue by limiting the maximum number of server registrations to 256 per node. If the NEW_SERVER message is received for an old port, then don't restrict it as it will get replaced. While at it, also rate limit the error messages in the failure path of qrtr_ns_worker(). Note that the limit of 256 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < b48fc702b20233b809f01053232c3cd5083c97b4 (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < 991c431077b19176d3fe3bb54054c063776a8cdc (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < 94914731ca0b99899dceadd80d2df00584a688ca (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < e6f6cd501fb54060940a6eb3f4103eeb5e426ae7 (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < 3efaad55cad1ded429e3a873bfece389058a526b (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < 35fb4a0c077c5d1049c2628b769e0a1b1e65df0d (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < 868202aa2adae427060a42d5bd663b4d782ec02c (git)
Affected: 0c2204a4ad710d95d348ea006f14ba926e842ffd , < d5ee2ff98322337951c56398e79d51815acbf955 (git)
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Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 5.10.265 , ≤ 5.10.* (semver)
Unaffected: 5.15.216 , ≤ 5.15.* (semver)
Unaffected: 6.1.183 , ≤ 6.1.* (semver)
Unaffected: 6.6.140 , ≤ 6.6.* (semver)
Unaffected: 6.12.86 , ≤ 6.12.* (semver)
Unaffected: 6.18.27 , ≤ 6.18.* (semver)
Unaffected: 7.0.4 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net: qrtr: ns: Limit the maximum server registration per node",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43491.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-31T17:03:26Z",
      "cve": "CVE-2026-43491",
      "id": "CVE-2026-43491",
      "initial_release_date": "2026-05-20T02:28:27Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "528",
      "product_status:known_not_affected": "175",
      "product_status:recommended": "283",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43491",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43491.json",
      "version": "19"
    }
  }
}



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Taxonomy of the tags.





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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.