Vulnerability-Lookup

FKIE_CVE-2026-43383

Vulnerability from fkie_nvd - Published: 2026-05-08 15:16 - Updated: 2026-05-26 17:07

Severity

9.4 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
  "configurations": [
    {
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        {
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    }
  ],
  "id": "CVE-2026-43383",
  "lastModified": "2026-05-26T17:07:21.210",
  "metrics": {
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      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.4,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "LOW",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H",
          "version": "3.1"
        },
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        "impactScore": 5.5,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
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  "published": "2026-05-08T15:16:49.593",
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
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      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-43383 (GCVE-0-2026-43383)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-05-11 22:23

Title

net/tcp-md5: Fix MAC comparison to be constant-time

Summary

Severity

9.4 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

Assigner

Linux

References

7 references

URL	Tags
https://git.kernel.org/stable/c/821c8751fdeecdeec…
https://git.kernel.org/stable/c/345a9530756528d7c…
https://git.kernel.org/stable/c/5d305a95130a8d08b…
https://git.kernel.org/stable/c/02669e2a4d207068e…
https://git.kernel.org/stable/c/ae3831b44f477de04…
https://git.kernel.org/stable/c/b502e97e29d791ff7…
https://git.kernel.org/stable/c/46d0d6f50dab70663…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < 821c8751fdeecdeecabeb11704dd33439c9e4bbc (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < 345a9530756528d7ca407663d659c3c40e75c3dd (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < 5d305a95130a8d08b9545e47f1e18d29d59866cb (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < 02669e2a4d207068edce7e8b5fafd85822018ce6 (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < ae3831b44f477de048287493e184fc3ff913b624 (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < b502e97e29d791ff7a8051f29a414535739be218 (git) Affected: cfb6eeb4c860592edd123fdea908d23c6ad1c7dc , < 46d0d6f50dab706637f4c18a470aac20a21900d3 (git)
Linux	Linux	Affected: 2.6.20 Unaffected: 0 , < 2.6.20 (semver) Unaffected: 5.10.253 , ≤ 5.10.* (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)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/Kconfig",
            "net/ipv4/tcp.c",
            "net/ipv4/tcp_ipv4.c",
            "net/ipv6/tcp_ipv6.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
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            },
            {
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              "version": "0",
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              "versionType": "semver"
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              "versionType": "semver"
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              "version": "6.6.130",
              "versionType": "semver"
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              "versionType": "semver"
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              "version": "7.0",
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      "title": "net/tcp-md5: Fix MAC comparison to be constant-time",
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}

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.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-43383

CVE-2026-43383 (GCVE-0-2026-43383)

Tags

Sightings

Nomenclature