CVE-2023-53600 (GCVE-0-2023-53600)
Vulnerability from cvelistv5 – Published: 2025-10-04 15:44 – Updated: 2026-08-05 09:15
VLAI
EPSS
VEX
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)
Assigner
References
Impacted products
2 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) |
guessed | |
| 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) |
guessed |
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}
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}
],
"id": "CVE-2023-53600",
"lastModified": "2026-08-04T10:19:14.090",
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"id": "CVE-2023-53600",
"initial_release_date": "2023-01-01T00:00:00+00:00",
"product_status:known_affected": "170",
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"source": "Red Hat CSAF VEX",
"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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"cve": "CVE-2023-53600",
"id": "CVE-2023-53600",
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"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2023-53600",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-53600.json",
"version": "44"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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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.
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