CVE-2026-23274 (GCVE-0-2026-23274)

Vulnerability from cvelistv5 – Published: 2026-03-20 08:08 – Updated: 2026-05-11 22:03
VLAI
Title
netfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels IDLETIMER revision 0 rules reuse existing timers by label and always call mod_timer() on timer->timer. If the label was created first by revision 1 with XT_IDLETIMER_ALARM, the object uses alarm timer semantics and timer->timer is never initialized. Reusing that object from revision 0 causes mod_timer() on an uninitialized timer_list, triggering debugobjects warnings and possible panic when panic_on_warn=1. Fix this by rejecting revision 0 rule insertion when an existing timer with the same label is of ALARM type.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 32e937dc6e97f5ed3cdfe3fc0b2b19a05e23fa44 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 144f88054ba0180467356f40895bd660b5dceeec (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 28c7cfaf0c0ab17cbd7754092116fd1af45271f9 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 54080355999381fed4a26129579a5765bab87491 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 5e7ece24c5cb75a60402aad4d803c7898ea40aa9 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < f5ef97c13165542480a6ffdbe6f09f40bbb7cbf1 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < f228b9ae2a7e84d1153616d8e71c4236cb1f1309 (git)
Affected: 68983a354a655c35d3fb204489d383a2a051fda7 , < 329f0b9b48ee6ab59d1ab72fef55fe8c6463a6cf (git)
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Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (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: 6.18.19 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  }
}


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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

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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.