Kernel memory disclosure and crash via length overflow
Published May 8, 2026 · Updated May 8, 2026
Out-of-bounds read in Linux Kernel libceph allows remote attackers to read kernel memory or crash the client via a crafted auth reply. ceph_handle_auth_reply stores payload_len as a signed int, so values above INT_MAX become negative and move the decode pointer before the message buffer because ceph_decode_need checks only the allocation end. Reachability requires an affected Ceph kernel client to connect or reconnect to a malicious, compromised, or impersonated monitor; no target credentials or user interaction are required, and the path provides no write primitive.
Summary
What happened
Out-of-bounds read in Linux Kernel libceph allows remote attackers to read kernel memory or crash the client via a crafted auth reply. ceph_handle_auth_reply stores payload_len as a signed int, so values above INT_MAX become negative and move the decode pointer before the message buffer because ceph_decode_need checks only the allocation end. Reachability requires an affected Ceph kernel client to connect or reconnect to a malicious, compromised, or impersonated monitor; no target credentials or user interaction are required, and the path provides no write primitive.
The record
- CVE
- CVE-2026-43407
- Published
- May 8, 2026
- Updated
- May 8, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 8, 2026CVE publishedPublication date reported by the CVE source.
- May 8, 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?
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- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <6cee34d6669fe176b4259131adb1a145c939b472
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8bb87547e92dcf0928ed763c60e0ac8d733c3656
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9f9e2297f45fc2d2524eb104c289d69ddef95665
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b282c43ed156ae15ea76748fc15cd5c39dc9ab72
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ea080b21092590122c3f971cf588932cdbf47847
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ed024d2f4c79c0eb2464df0fb640610ac301f9a0
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <edc678e5cd11730a2834b43071d8923f05bc334d
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f9da5c1bbac5c8e33259fe00ed7347438fffa969
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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