Back to CVE records
High 7.8Published Mar 20, 2026

CVE-2026-23274netfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels

Updated under an hour ago ()

Does this affect you?

It affects Linux and 5 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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.

CVSS
7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE)
Not given
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
Linux
NVD analysis
Modified
Record last updated
Oct 16, 2026
First seen by InfoSec Signals
Oct 9, 2026

Affected products

Affected products
Linux Linux
linux:linux (from the name)
68983a354a655c35d3fb204489d383a2a051fda7 builds before 32e937dc6e97f5ed3cdfe3fc0b2b19a05e23fa44; 68983a354a655c35d3fb204489d383a2a051fda7 builds before 144f88054ba0180467356f40895bd660b5dceeec; 68983a354a655c35d3fb204489d383a2a051fda7 builds before 28c7cfaf0c0ab17cbd7754092116fd1af45271f9; from 68983a354a655c35d3fb204489d383a2a051fda7 before 54080355999381fed4a26129579a5765bab87491; 68983a354a655c35d3fb204489d383a2a051fda7 builds before 5e7ece24c5cb75a60402aad4d803c7898ea40aa9; from 68983a354a655c35d3fb204489d383a2a051fda7 before f5ef97c13165542480a6ffdbe6f09f40bbb7cbf1; from 68983a354a655c35d3fb204489d383a2a051fda7 before f228b9ae2a7e84d1153616d8e71c4236cb1f1309; 68983a354a655c35d3fb204489d383a2a051fda7 builds before 329f0b9b48ee6ab59d1ab72fef55fe8c6463a6cf
CNA record
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)
from V3.1.6
CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)
from V3.1.6
CISA ADP
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)
all versions
CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)
from V3.1.6
CISA ADP
linux linux_kernel
linux:linux_kernel
from 5.7 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.167; from 6.2 before 6.6.130; from 6.7 before 6.12.78; from 6.13 before 6.18.19; from 6.19 before 6.19.9; 7.0; and 2 more ranges
NVD

References

  • patch
  • patch
  • patch
  • patch
  • patch
  • patch
  • patch
  • patch

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.