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EUVD-2026-364700
European Vulnerability Database identifier assigned by ENISAReserved
2026-10-02 08:33
Assigner
ENISA
Alias of
a CVE record, shown under related vulnerabilities.
This identifier carries no description, severity or references of its own:
they belong to that CVE.
{
"assigner": "ENISA",
"date_reserved": "2026-10-02T08:33:38.989811+00:00",
"id": "EUVD-2026-364700"
}
CVE-2026-23398 (GCVE-0-2026-23398)
Vulnerability from cvelistv5 – Published: 2026-03-26 10:22 – Updated: 2026-09-08 08:45
VLAI
EPSS
VEX
Title
icmp: fix NULL pointer dereference in icmp_tag_validation()
Summary
In the Linux kernel, the following vulnerability has been resolved:
icmp: fix NULL pointer dereference in icmp_tag_validation()
icmp_tag_validation() unconditionally dereferences the result of
rcu_dereference(inet_protos[proto]) without checking for NULL.
The inet_protos[] array is sparse -- only about 15 of 256 protocol
numbers have registered handlers. When ip_no_pmtu_disc is set to 3
(hardened PMTU mode) and the kernel receives an ICMP Fragmentation
Needed error with a quoted inner IP header containing an unregistered
protocol number, the NULL dereference causes a kernel panic in
softirq context.
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143)
Call Trace:
<IRQ>
icmp_rcv (net/ipv4/icmp.c:1527)
ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207)
ip_local_deliver_finish (net/ipv4/ip_input.c:242)
ip_local_deliver (net/ipv4/ip_input.c:262)
ip_rcv (net/ipv4/ip_input.c:573)
__netif_receive_skb_one_core (net/core/dev.c:6164)
process_backlog (net/core/dev.c:6628)
handle_softirqs (kernel/softirq.c:561)
</IRQ>
Add a NULL check before accessing icmp_strict_tag_validation. If the
protocol has no registered handler, return false since it cannot
perform strict tag validation.
Severity
No CVSS data available.
Assigner
References
10 references
Impacted products
8 products
| Vendor | Product | Version | |
|---|---|---|---|
| Linux | Linux |
Affected:
8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < 571d9d7b650f02d1e38c01128817868bceac9edd
(git)
Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < d783fa413c702ff0f8f8bea63f862e28eeaf39e3 (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < 1f9f2c6d4b2a613b7756fc5679c5116ba2ca0161 (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < b61529c357f1ee4d64836eb142a542d2e7ad67ce (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < 9647e99d2a617c355d2b378be0ff6d0e848fd579 (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < d938dd5a0ad780c891ea3bc94cae7405f11e618a (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < 1e4e2f5e48cec0cccaea9815fb9486c084ba41e2 (git) Affected: 8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e , < 614aefe56af8e13331e50220c936fc0689cf5675 (git) |
|
| Linux | Linux |
Affected:
3.14
Unaffected: 0 , < 3.14 (semver) Unaffected: 5.10.253 , ≤ 5.10.* (semver) Unaffected: 5.15.203 , ≤ 5.15.* (semver) Unaffected: 6.1.167 , ≤ 6.1.* (semver) Unaffected: 6.6.130 , ≤ 6.6.* (semver) Unaffected: 6.12.78 , ≤ 6.12.* (semver) Unaffected: 6.18.20 , ≤ 6.18.* (semver) Unaffected: 6.19.10 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix) |
|
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.5 , < *
(custom)
|
|
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
|
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < *
(custom)
|
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],
"providerMetadata": {
"dateUpdated": "2026-09-08T08:45:59.359Z",
"orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"shortName": "siemens-SADP"
},
"references": [
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
}
],
"x_adpType": "supplier"
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],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
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],
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"descriptions": [
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"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nicmp: fix NULL pointer dereference in icmp_tag_validation()\n\nicmp_tag_validation() unconditionally dereferences the result of\nrcu_dereference(inet_protos[proto]) without checking for NULL.\nThe inet_protos[] array is sparse -- only about 15 of 256 protocol\nnumbers have registered handlers. When ip_no_pmtu_disc is set to 3\n(hardened PMTU mode) and the kernel receives an ICMP Fragmentation\nNeeded error with a quoted inner IP header containing an unregistered\nprotocol number, the NULL dereference causes a kernel panic in\nsoftirq context.\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]\n RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143)\n Call Trace:\n \u003cIRQ\u003e\n icmp_rcv (net/ipv4/icmp.c:1527)\n ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207)\n ip_local_deliver_finish (net/ipv4/ip_input.c:242)\n ip_local_deliver (net/ipv4/ip_input.c:262)\n ip_rcv (net/ipv4/ip_input.c:573)\n __netif_receive_skb_one_core (net/core/dev.c:6164)\n process_backlog (net/core/dev.c:6628)\n handle_softirqs (kernel/softirq.c:561)\n \u003c/IRQ\u003e\n\nAdd a NULL check before accessing icmp_strict_tag_validation. If the\nprotocol has no registered handler, return false since it cannot\nperform strict tag validation."
}
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{
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"title": "icmp: fix NULL pointer dereference in icmp_tag_validation()",
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"cveId": "CVE-2026-23398",
"datePublished": "2026-03-26T10:22:50.606Z",
"dateReserved": "2026-01-13T15:37:46.012Z",
"dateUpdated": "2026-09-08T08:45:59.359Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
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}
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Trend slope:
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(linear fit over daily sighting counts)
Show additional events:
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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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