Authenticated memory disclosure via compressed-token counter overflow
Published May 20, 2026 · Updated Aug 25, 2026
Integer overflow in rsync 3.4.2 and earlier allows remote authenticated users to disclose receiver process memory via compressed tokens. The recv_deflated_token, recv_zstd_token, and recv_compressed_token decoders increment rx_token without checking for signed 32-bit overflow. An authenticated daemon connection with compression enabled is required, and exposed data includes environment variables, passwords, and memory pointers.
Summary
What happened
Integer overflow in rsync 3.4.2 and earlier allows remote authenticated users to disclose receiver process memory via compressed tokens. The recv_deflated_token, recv_zstd_token, and recv_compressed_token decoders increment rx_token without checking for signed 32-bit overflow. An authenticated daemon connection with compression enabled is required, and exposed data includes environment variables, passwords, and memory pointers.
The record
- CVE
- CVE-2026-43618
- Published
- May 20, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-200, CWE-190, T1005
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 20, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
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Published CVSS scores
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Attacks
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Technologies
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