High
Security advisory
Redis is an open source, in-memory database that persists on disk. The redis-cli command line tool and redis-sentinel service may be vulnerable to integer overflow when parsing specially crafted large multi-bulk network replies. This is a result of a vulnerability in the underlying hiredis library which does not perform an overflow check before calling the calloc() heap allocation function. This issue only impacts systems with heap allocators that do not perform their own overflow checks. Most modern systems do and are therefore not likely to be affected. Furthermore, by default redis-sentinel uses the jemalloc allocator which is also not vulnerable. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-32762
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 09:27 UTC · Revision 1
Source evidence
Redis is an open source, in-memory database that persists on disk. The redis-cli command line tool and redis-sentinel service may be vulnerable to integer overflow when parsing specially crafted large multi-bulk network replies. This is a result of a vulnerability in the underlying hiredis library which does not perform an overflow check before calling the calloc() heap allocation function. This issue only impacts systems with heap allocators that do not perform their own overflow checks. Most modern systems do and are therefore not likely to be affected. Furthermore, by default redis-sentinel uses the jemalloc allocator which is also not vulnerable. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14.
osv:CVE-2021-32762
Complete source record
{
"id": "5735aed165ab06f6c0a9450b610feae9a63165a4ae251b8f9dc48b8e048fee0a",
"url": "https://osv.dev/vulnerability/CVE-2021-32762",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-32762",
"summary": "Redis is an open source, in-memory database that persists on disk. The redis-cli command line tool and redis-sentinel service may be vulnerable to integer overflow when parsing specially crafted large multi-bulk network replies. This is a result of a vulnerability in the underlying hiredis library which does not perform an overflow check before calling the calloc() heap allocation function. This issue only impacts systems with heap allocators that do not perform their own overflow checks. Most modern systems do and are therefore not likely to be affected. Furthermore, by default redis-sentinel uses the jemalloc allocator which is also not vulnerable. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14.",
"evidence": "osv:CVE-2021-32762",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2021-32762",
"aliases": [
"BIT-keydb-2021-32762",
"BIT-redis-2021-32762",
"BIT-valkey-2021-32762",
"CVE-2021-32762",
"GHSA-833w-8v3m-8wwr"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/redis/redis",
"type": "GIT",
"events": [
{
"introduced": "882ca6962f4ca32683b0e8db831de1b425c27d3c"
},
{
"fixed": "704ba5f5b22ae1ecafbcfb7a3258311c27ff94ff"
},
{
"introduced": "17dfd7cabbf7954f92b7a1243d4bb27fee5d4500"
},
{
"fixed": "5895d119b1c2825ff0394f30e246e036c3972bc5"
},
{
"introduced": "445aa844b946a8f1bc21ac8554b44adb1ecb4018"
},
{
"fixed": "4930d19e70c391750479951022e207e19111eb55"
},
{
"fixed": "0215324a66af949be39b34be2d55143232c1cb71"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:redis:redis:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.0.14"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:redis:redis:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "6.0.0"
},
{
"fixed": "6.0.16"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:redis:redis:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "6.2.0"
},
{
"fixed": "6.2.6"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "0215324a66af949be39b34be2d55143232c1cb71"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"6.2.5",
"6.0.15",
"5.0.13",
"5.0.12",
"6.0.14",
"6.2.4",
"6.2.3",
"6.0.13",
"6.2.2",
"6.0.12",
"6.2.1",
"6.2.0",
"6.0.11",
"5.0.11",
"5.0.10",
"6.0.10",
"6.0.9",
"6.0.8",
"6.0.7",
"6.0.6",
"6.0.5",
"6.0.4",
"6.0.3",
"6.0.2",
"6.0.1",
"6.0.0",
"5.0.9",
"5.0.8",
"5.0.7",
"5.0.6",
"5.0.5",
"5.0.4",
"5.0.3",
"5.0.2",
"5.0.1",
"5.0.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-32762.json",
"vanir_signatures": [
{
"id": "CVE-2021-32762-3e4b08f6",
"digest": {
"length": 6546,
"function_hash": "160136926384499477379751229509923238067"
},
"source": "https://github.com/redis/redis/commit/0215324a66af949be39b34be2d55143232c1cb71",
"target": {
"file": "deps/hiredis/test.c",
"function": "test_reply_reader"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2021-32762-4ae63639",
"digest": {
"length": 581,
"function_hash": "179161735348210698687051920573265359593"
},
"source": "https://github.com/redis/redis/commit/0215324a66af949be39b34be2d55143232c1cb71",
"target": {
"file": "deps/hiredis/hiredis.c",
"function": "createArrayObject"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2021-32762-8a67fc88",
"digest": {
"threshold": 0.9,
"line_hashes": [
"311195162694762926584360255253075821286",
"34398200280396169294640070927249867179",
"76188935927609120202871962455023382498",
"186027357458498207079532665570846242970"
]
},
"source": "https://github.com/redis/redis/commit/0215324a66af949be39b34be2d55143232c1cb71",
"target": {
"file": "deps/hiredis/hiredis.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
},
{
"id": "CVE-2021-32762-c084ea7c",
"digest": {
"threshold": 0.9,
"line_hashes": [
"2960801188689279389740907912361228292",
"103680156091366763705168315892522468615",
"313519843436751110082004899014515685551"
]
},
"source": "https://github.com/redis/redis/commit/0215324a66af949be39b34be2d55143232c1cb71",
"target": {
"file": "deps/hiredis/test.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-24T14:25:12Z"
}
}
],
"modified": "2026-10-24T14:25:12.816474160Z",
"provider": "osv",
"references": [
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HTYQ5ZF37HNGTZWVNJD3VXP7I6MEEF42/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VL5KXFN3ATM7IIM7Q4O4PWTSRGZ5744Z/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WR5WKJWXD4D6S3DJCZ56V74ESLTDQRAB/",
"https://github.com/redis/redis/security/advisories/GHSA-833w-8v3m-8wwr",
"https://security.gentoo.org/glsa/202209-17",
"https://security.netapp.com/advisory/ntap-20211104-0003/",
"https://www.debian.org/security/2021/dsa-5001",
"https://github.com/redis/redis/commit/0215324a66af949be39b34be2d55143232c1cb71",
"https://www.oracle.com/security-alerts/cpuapr2022.html"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "10.0"
},
{
"last_affected": "10.0"
},
{
"introduced": "11.0"
},
{
"last_affected": "11.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "33"
},
{
"last_affected": "33"
},
{
"introduced": "34"
},
{
"last_affected": "34"
},
{
"introduced": "35"
},
{
"last_affected": "35"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:oracle:communications_operations_monitor:4.3:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:communications_operations_monitor:4.4:*:*:*:*:*:*:*",
"cpe:2.3:a:oracle:communications_operations_monitor:5.0:*:*:*:*:*:*:*"
],
"vendor_product": "oracle:communications_operations_monitor",
"extracted_events": [
{
"range": [
{
"introduced": "4.3"
},
{
"last_affected": "4.3"
},
{
"introduced": "4.4"
},
{
"last_affected": "4.4"
},
{
"introduced": "5.0"
},
{
"last_affected": "5.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-32762",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 443741,
"published_at": "2021-10-04T18:15:09.043+00:00"
}