CriticalFix available
net/tcp-md5: Fix MAC comparison to be constant-time
Type: advisorySources: OSV
In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.10.253, 5.15.210, 6.1.167, 6.12.78, 6.18.19, 6.19.9, 6.6.130
- CVEs
- CVE-2026-43383
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 04:59 UTC · Revision 1
Source evidence
net/tcp-md5: Fix MAC comparison to be constant-time
core-osv · Original sourcePublished 8 May 2026, 14:21 UTC
In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.
osv:CVE-2026-43383
Kernel
Fixed versions: 5.10.253, 5.15.210, 6.1.167, 6.6.130, 6.12.78, 6.18.19, 6.19.9
Complete source record
{
"id": "77e56298a6c5e251396f38dae51e2b3fe0d4aa85cccbac0b13694f1e78526d53",
"url": "https://osv.dev/vulnerability/CVE-2026-43383",
"method": "structured",
"payload": {
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"title": "net/tcp-md5: Fix MAC comparison to be constant-time",
"summary": "In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.",
"evidence": "osv:CVE-2026-43383",
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"metrics": [
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{
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"package": {
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"ecosystem": "Linux"
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"database_specific": {
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"modified": "2026-10-28T02:30:25.979763900Z",
"provider": "osv",
"references": [
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"https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd",
"https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3",
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"https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc",
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"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43383.json",
"https://nvd.nist.gov/vuln/detail/CVE-2026-43383",
"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
],
"provider_metadata": {
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43383.json"
}
},
"related_cves": [
{
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"evidence": "/id"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 492625,
"published_at": "2026-05-08T14:21:30.704+00:00"
}