Remote service crash via overstated allocation size
Published Mar 31, 2021 · Updated Aug 3, 2024
Heap overflow in Redis before 5.0.10, before 6.0.9, and before 6.2.0 allows remote attackers to crash the server via crafted requests. The zmalloc_size() function rounds a stored allocation size up to a long boundary on systems without malloc_usable_size(), overstating the writable buffer length. Only builds using allocators other than jemalloc or glibc malloc are affected; the erroneous size can drive an out-of-bounds write and terminate the Redis process.
Summary
What happened
Heap overflow in Redis before 5.0.10, before 6.0.9, and before 6.2.0 allows remote attackers to crash the server via crafted requests. The zmalloc_size() function rounds a stored allocation size up to a long boundary on systems without malloc_usable_size(), overstating the writable buffer length. Only builds using allocators other than jemalloc or glibc malloc are affected; the erroneous size can drive an out-of-bounds write and terminate the Redis process.
The record
- CVE
- CVE-2021-3470
- Published
- Mar 31, 2021
- Updated
- Aug 3, 2024
- Vendor
- Redis
- Product
- Redis
- Classifications
- CWE-119, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 31, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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.
- Affected versionversion=redis 5.0.10, redis 6.0.9, redis 6.2.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
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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