CVE-2021-32675
mediumpriority · attend · 46EPSS 0.161 · 97 %ileexploit · PoCDEEURUUSEPSS · scored 2026-10-27
Redis is an open source, in-memory database that persists on disk. When parsing an incoming Redis Standard Protocol (RESP) request, Redis allocates memory according to user-specified values which determine the number of elements (in the multi-bulk header) and size of each element (in the bulk header). An attacker delivering specially crafted requests over multiple connections can cause the server to allocate significant amount of memory. Because the same parsing mechanism is used to handle authentication requests, this vulnerability can also be exploited by unauthenticated users. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate this problem without patching the redis-server executable is to block access to prevent unauthenticated users from connecting to Redis. This can be done in different ways: Using network access control tools like firewalls, iptables, security groups, etc. or Enabling TLS and requiring users to authenticate using client side certificates.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
- rubbxalc/CVE-2021-32675rubbxalc/CVE-2021-32675PoC · poc_in_github
affected products (38)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2022-1579Redis: Mehrere SchwachstellenDeutsch2021-10-04csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Redis ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen oder einen Denial of Service Zustand herbeizuführen.
- BIT-keydb-2021-32675DoS vulnerability in Redis2024-08-22vendor · osvUS
Redis is an open source, in-memory database that persists on disk. When parsing an incoming Redis Standard Protocol (RESP) request, Redis allocates memory according to user-specified values which determine the number of elements (in the multi-bulk header) and size of each element (in the bulk header). An attacker delivering specially crafted requests over multiple connections can cause the server to allocate significant amount of memory. Because the same parsing mechanism is used to handle authentication requests, this vulnerability can also be exploited by unauthenticated users. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate this problem without patching the redis-server executable is to block access to prevent unauthenticated users from connecting to Redis. This can be done in different ways: Using network access control tools like firewalls, iptables, security groups, etc. or Enabling TLS and requiring users to authenticate using client side certificates.
- BIT-redis-2021-32675DoS vulnerability in Redis2024-03-06vendor · osvUS
Redis is an open source, in-memory database that persists on disk. When parsing an incoming Redis Standard Protocol (RESP) request, Redis allocates memory according to user-specified values which determine the number of elements (in the multi-bulk header) and size of each element (in the bulk header). An attacker delivering specially crafted requests over multiple connections can cause the server to allocate significant amount of memory. Because the same parsing mechanism is used to handle authentication requests, this vulnerability can also be exploited by unauthenticated users. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate this problem without patching the redis-server executable is to block access to prevent unauthenticated users from connecting to Redis. This can be done in different ways: Using network access control tools like firewalls, iptables, security groups, etc. or Enabling TLS and requiring users to authenticate using client side certificates.
- BIT-valkey-2021-32675DoS vulnerability in Redis2024-08-22vendor · osvUS
Redis is an open source, in-memory database that persists on disk. When parsing an incoming Redis Standard Protocol (RESP) request, Redis allocates memory according to user-specified values which determine the number of elements (in the multi-bulk header) and size of each element (in the bulk header). An attacker delivering specially crafted requests over multiple connections can cause the server to allocate significant amount of memory. Because the same parsing mechanism is used to handle authentication requests, this vulnerability can also be exploited by unauthenticated users. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate this problem without patching the redis-server executable is to block access to prevent unauthenticated users from connecting to Redis. This can be done in different ways: Using network access control tools like firewalls, iptables, security groups, etc. or Enabling TLS and requiring users to authenticate using client side certificates.
also known as (7)
Other names and identifiers for this entity.
- CNNVD-202110-137cnnvd
- EUVD-2021-19484enisa_euvd
- BDU:2021-04962fstec_bdu
- BIT-keydb-2021-32675osv
- BIT-redis-2021-32675osv
- BIT-valkey-2021-32675osv
- GHSA-f6pw-v9gw-v64posv
sources
Which sources assert this record, and when.
references (55)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2021-32675cnnvd
- https://github.com/redis/redis/commit/5674b0057ff2903d43eaff802017eddf37c360f8cnnvd
- https://github.com/redis/redis/security/advisories/GHSA-f6pw-v9gw-v64pcnnvd
- https://lists.apache.org/thread.html/ra603ff6e04549d7f290f61f9b11e2d2e4dba693b05ff053f4ec6bc47@%3Cnotifications.geode.apache.org%3Ecnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HTYQ5ZF37HNGTZWVNJD3VXP7I6MEEF42/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VL5KXFN3ATM7IIM7Q4O4PWTSRGZ5744Z/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WR5WKJWXD4D6S3DJCZ56V74ESLTDQRAB/cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-32675cnnvd
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