Vulnerability-Lookup

FKIE_CVE-2026-31640

Vulnerability from fkie_nvd - Published: 2026-04-24 15:16 - Updated: 2026-06-17 10:34

Severity

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

Summary

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix use of wrong skb when comparing queued RESP challenge serial In rxrpc_post_response(), the code should be comparing the challenge serial number from the cached response before deciding to switch to a newer response, but looks at the newer packet private data instead, rendering the comparison always false. Fix this by switching to look at the older packet. Fix further[1] to substitute the new packet in place of the old one if newer and also to release whichever we don't use.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/20386e7f8d97475b8d815873e246423317ec4260	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/9132b1a7bf83b4a8042fffbc99d075b727a16742	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b33f5741bb187db8ff32e8f5b96def77cc94dfca	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.16
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/trace/events/rxrpc.h",
            "net/rxrpc/conn_event.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9132b1a7bf83b4a8042fffbc99d075b727a16742",
              "status": "affected",
              "version": "5800b1cf3fd8ccab752a101865be1e76dac33142",
              "versionType": "git"
            },
            {
              "lessThan": "20386e7f8d97475b8d815873e246423317ec4260",
              "status": "affected",
              "version": "5800b1cf3fd8ccab752a101865be1e76dac33142",
              "versionType": "git"
            },
            {
              "lessThan": "b33f5741bb187db8ff32e8f5b96def77cc94dfca",
              "status": "affected",
              "version": "5800b1cf3fd8ccab752a101865be1e76dac33142",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/trace/events/rxrpc.h",
            "net/rxrpc/conn_event.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.23",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: Fix use of wrong skb when comparing queued RESP challenge serial\n\nIn rxrpc_post_response(), the code should be comparing the challenge serial\nnumber from the cached response before deciding to switch to a newer\nresponse, but looks at the newer packet private data instead, rendering the\ncomparison always false.\n\nFix this by switching to look at the older packet.\n\nFix further[1] to substitute the new packet in place of the old one if\nnewer and also to release whichever we don\u0027t use."
    }
  ],
  "id": "CVE-2026-31640",
  "lastModified": "2026-06-17T10:34:08.743",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
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        "impactScore": 3.6,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-04-24T15:16:43.357",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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      "url": "https://git.kernel.org/stable/c/20386e7f8d97475b8d815873e246423317ec4260"
    },
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    },
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  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "description": [
        {
          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-31640 (GCVE-0-2026-31640)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:44 – Updated: 2026-08-05 12:24

Title

rxrpc: Fix use of wrong skb when comparing queued RESP challenge serial

Summary

Severity

7.5 (High)


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

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/9132b1a7bf83b4a80…
https://git.kernel.org/stable/c/20386e7f8d97475b8…
https://git.kernel.org/stable/c/b33f5741bb187db8f…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < 9132b1a7bf83b4a8042fffbc99d075b727a16742 (git) Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < 20386e7f8d97475b8d815873e246423317ec4260 (git) Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < b33f5741bb187db8ff32e8f5b96def77cc94dfca (git)
Linux	Linux	Affected: 6.16 Unaffected: 0 , < 6.16 (semver) Unaffected: 6.18.23 , ≤ 6.18.* (semver) Unaffected: 6.19.13 , ≤ 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": [
            "include/trace/events/rxrpc.h",
            "net/rxrpc/conn_event.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9132b1a7bf83b4a8042fffbc99d075b727a16742",
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              "versionType": "git"
            },
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              "version": "5800b1cf3fd8ccab752a101865be1e76dac33142",
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            },
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              "version": "5800b1cf3fd8ccab752a101865be1e76dac33142",
              "versionType": "git"
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          ]
        },
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          "product": "Linux",
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          ],
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          "vendor": "Linux",
          "versions": [
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            },
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              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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FKIE_CVE-2026-31640

CVE-2026-31640 (GCVE-0-2026-31640)

Tags

Sightings

Nomenclature

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