CVE-2026-74434Network attack vector

Kernel memory corruption via peeked RxRPC challenge

Published Aug 15, 2026 · Updated Aug 15, 2026

Use-after-free in the Linux kernel 6.16 allows remote attackers to corrupt kernel memory through a crafted RxRPC challenge. rxrpc_recvmsg_oob() leaves a MSG_PEEK challenge skb on recvmsg_oobq while also inserting its shared rbnode into pending_oobq, overwriting list links and causing both queues to free one reference. Reachability requires an AF_RXRPC client to process the peer's challenge; closing the socket then triggers invalid pointer writes, a double free, and connection-reference underflow that can panic the kernel or enable kernel code execution.

CVSS severity9.8
Critical
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Linux kernel 6.16 allows remote attackers to corrupt kernel memory through a crafted RxRPC challenge. rxrpc_recvmsg_oob() leaves a MSG_PEEK challenge skb on recvmsg_oobq while also inserting its shared rbnode into pending_oobq, overwriting list links and causing both queues to free one reference. Reachability requires an AF_RXRPC client to process the peer's challenge; closing the socket then triggers invalid pointer writes, a double free, and connection-reference underflow that can panic the kernel or enable kernel code execution.

The record

CVE
CVE-2026-74434
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5800b1cf3fd8ccab752a101865be1e76dac33142 <5801cff7d5d7b4e9d877dfb627b23eb63167f02c
  2. Affected versionversion=5800b1cf3fd8ccab752a101865be1e76dac33142 <5f470cc883416fea6d3bce18ef96bf91dd49ffc3
  3. Affected versionversion=5800b1cf3fd8ccab752a101865be1e76dac33142 <9ada3931beb37068fcb725b34b0398457009f343
  4. Affected versionversion=6.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5800b1cf3fd8ccab752a101865be1e76dac33142 <5801cff7d5d7b4e9d877dfb627b23eb63167f02c; version=5800b1cf3fd8ccab752a101865be1e76dac33142 <5f470cc883416fea6d3bce18ef96bf91dd49ffc3; version=5800b1cf3fd8ccab752a101865be1e76dac33142 <9ada3931beb37068fcb725b34b0398457009f343; version=6.16

Published CVSS scores

9.8Linux CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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