Hiredis
CVE-2021-32765
HIGH
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Integer overflow checks
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 8.8 (HIGH). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could cause unexpected behavior through arithmetic overflow by sending crafted requests to the affected application. |
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Alert meAnalysisAI
Hiredis is a minimalistic C client library for the Redis database. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Validate arithmetic operations, use safe integer libraries, check bounds before allocation.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Integer Overflow (CWE-190), which allows attackers to cause unexpected behavior through arithmetic overflow. Hiredis is a minimalistic C client library for the Redis database. In affected versions Hiredis is vulnurable to integer overflow if provided maliciously crafted or corrupted RESP mult-bulk protocol data. When parsing multi-bulk (array-like) replies, hiredis fails to check if count * sizeof(redisReply*) can be represented in SIZE_MAX. If it can not, and the calloc() call doesn't itself make this check, it would result in a short allocation and subsequent buffer overflow. Users of hiredis who are unable to update may set the maxelements context option to a value small enough that no overflow is possible. Affected products include: Redis Hiredis, Debian Debian Linux, Netapp Management Services For Element Software And Netapp Hci.
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Hiredis is a minimalistic C client library for the Redis database. In affected versions Hiredis is vulnurable to integer overflow if provided maliciously crafted or corrupted RESP mult-bulk protocol data. When parsing multi-bulk (array-like) replies, hiredis fails to check if count * sizeof(redisReply*) can be represented in SIZE_MAX. If it can not, and the calloc() call doesn't itself make this check, it would result in a short allocation and subsequent buffer overflow. Users of hiredis who are unable to update may set the maxelements context option to a value small enough that no overflow is possible.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
Integer overflow occurs when an arithmetic operation produces a result that exceeds the maximum value a given integer type can store.
Affected Products (CPE)NVD
async.c and dict.c in libhiredis.a in hiredis through 0.14.0 allow a NULL pointer dereference because malloc return valu
Denial of service in hiredis post-v1.5.0 (commit 29ea279) occurs when the RESP aggregate parser performs an uncontrolled
Exploit-DB