CVE-2023-53624
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq: fix integer overflow of "credit" if sch_fq is configured with "initial quantum" having values greater than INT_MAX, the first assignment of "credit" does signed integer overflow to a very negative value. In this situation, the syzkaller script provided by Cristoph triggers the CPU soft-lockup warning even with few sockets. It's not an infinite loop, but "credit" wasn't probably meant to be minus 2Gb for each new flow. Capping "initial quantum" to INT_MAX proved to fix the issue. v2: validation of "initial quantum" is done in fq_policy, instead of open coding in fq_change() _ suggested by Jakub Kicinski
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-10-07 16:15:45.190000
Last modified
2026-11-05 21:17:29.670000
View original CVE JSON
{
"id": "CVE-2023-53624",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-10-07T16:15:45.190",
"lastModified": "2026-11-05T21:17:29.670",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_fq: fix integer overflow of \"credit\"\n\nif sch_fq is configured with \"initial quantum\" having values greater than\nINT_MAX, the first assignment of \"credit\" does signed integer overflow to\na very negative value.\nIn this situation, the syzkaller script provided by Cristoph triggers the\nCPU soft-lockup warning even with few sockets. It's not an infinite loop,\nbut \"credit\" wasn't probably meant to be minus 2Gb for each new flow.\nCapping \"initial quantum\" to INT_MAX proved to fix the issue.\n\nv2: validation of \"initial quantum\" is done in fq_policy, instead of open\n coding in fq_change() _ suggested by Jakub Kicinski"
}
],
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"metrics": {
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{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
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"id": "CVE-2023-53624",
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"type": "Primary",
"description": [
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