CyberSecBulletin
CVE-2023-36824NVD status: Analyzed

redis: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2023-36824 is a high-severity out-of-bounds write vulnerability in redis, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 7.0.12 as the first without the flaw, so updating redis to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 77.4% chance of exploitation within 30 days, which is in the top 0.43% of all scored CVEs.

Patch now

Exploitation in the next 30 days is more likely than not, according to EPSS.

What to do

  1. Update redis to 7.0.12 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Redisredis>= 7.0.0, < 7.0.12; 7.0.0 up to, but not including, 7.0.127.0.12
Fedora ProjectFedora37; 38Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.4HighCNA (github.com)
CVSS 3.18.8HighNVD

Official description

Redis is an in-memory database that persists on disk. In Redit 7.0 prior to 7.0.12, extracting key names from a command and a list of arguments may, in some cases, trigger a heap overflow and result in reading random heap memory, heap corruption and potentially remote code execution. Several scenarios that may lead to authenticated users executing a specially crafted `COMMAND GETKEYS` or `COMMAND GETKEYSANDFLAGS`and authenticated users who were set with ACL rules that match key names, executing a specially crafted command that refers to a variadic list of key names. The vulnerability is patched in Redis 7.0.12.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Other vulnerabilities in redis

All redis vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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