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CVE-2023-53600 (GCVE-0-2023-53600)

Vulnerability from cvelistv5 – Published: 2025-10-04 15:44 – Updated: 2026-08-05 09:15
VLAI
Title
tunnels: fix kasan splat when generating ipv4 pmtu error
Summary
In the Linux kernel, the following vulnerability has been resolved: tunnels: fix kasan splat when generating ipv4 pmtu error If we try to emit an icmp error in response to a nonliner skb, we get BUG: KASAN: slab-out-of-bounds in ip_compute_csum+0x134/0x220 Read of size 4 at addr ffff88811c50db00 by task iperf3/1691 CPU: 2 PID: 1691 Comm: iperf3 Not tainted 6.5.0-rc3+ #309 [..] kasan_report+0x105/0x140 ip_compute_csum+0x134/0x220 iptunnel_pmtud_build_icmp+0x554/0x1020 skb_tunnel_check_pmtu+0x513/0xb80 vxlan_xmit_one+0x139e/0x2ef0 vxlan_xmit+0x1867/0x2760 dev_hard_start_xmit+0x1ee/0x4f0 br_dev_queue_push_xmit+0x4d1/0x660 [..] ip_compute_csum() cannot deal with nonlinear skbs, so avoid it. After this change, splat is gone and iperf3 is no longer stuck.
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: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f , < 5850c391fd7e25662334cb3cbf29a62bcbff1084 (git)
Affected: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f , < e95808121953410db8c59f0abfde70ac0d34222c (git)
Affected: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f , < da5f42a6e7485fbb7a6dbd6a2b3045e19e4df5cc (git)
Affected: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f , < fe6a9f7516735be9fdabab00e47ef7a3403a174d (git)
Affected: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f , < 6a7ac3d20593865209dceb554d8b3f094c6bd940 (git)
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Linux Linux Affected: 5.9
Unaffected: 0 , < 5.9 (semver)
Unaffected: 5.10.191 , ≤ 5.10.* (semver)
Unaffected: 5.15.127 , ≤ 5.15.* (semver)
Unaffected: 6.1.46 , ≤ 6.1.* (semver)
Unaffected: 6.4.11 , ≤ 6.4.* (semver)
Unaffected: 6.5 , ≤ * (original_commit_for_fix)
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      "status": "final",
      "title": "kernel: tunnels: fix kasan splat when generating ipv4 pmtu error",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-53600.json",
      "version": "3"
    }
  }
}



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Tags
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.