The version of redis installed on the remote host is prior to 6.2.6-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2REDIS6-2023-007 advisory.
Redis is an open source, in-memory database that persists on disk. In affected versions specially crafted Lua scripts executing in Redis can cause the heap-based Lua stack to be overflowed, due to incomplete checks for this condition. This can result with heap corruption and potentially remote code execution.
This problem exists in all versions of Redis with Lua scripting support, starting from 2.6. The problem is fixed in versions 6.2.6, 6.0.16 and 5.0.14. For users unable to update an additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from executing Lua scripts. This can be done using ACL to restrict EVAL and EVALSHA commands. (CVE-2021-32626)
Redis is an open source, in-memory database that persists on disk. In affected versions an integer overflow bug in Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves changing the default proto-max-bulk-len and client-query-buffer- limit configuration parameters to very large values and constructing specially crafted very large stream elements. The problem is fixed in Redis 6.2.6, 6.0.16 and 5.0.14. For users unable to upgrade an additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the proto-max-bulk-len configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command. (CVE-2021-32627)
Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the ziplist data structure used by all versions of Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves modifying the default ziplist configuration parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max- ziplist-value) to a very large value, and then constructing specially crafted commands to create very large ziplists. The problem is fixed in Redis versions 6.2.6, 6.0.16, 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the above configuration parameters. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command. (CVE-2021-32628)
Redis is an open source, in-memory database that persists on disk. When using the Redis Lua Debugger, users can send malformed requests that cause the debugger’s protocol parser to read data beyond the actual buffer. This issue affects all versions of Redis with Lua debugging support (3.2 or newer). The problem is fixed in versions 6.2.6, 6.0.16 and 5.0.14. (CVE-2021-32672)
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.
(CVE-2021-32675)
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.
(CVE-2021-32762)
Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the underlying string library can be used to corrupt the heap and potentially result with denial of service or remote code execution. The vulnerability involves changing the default proto-max-bulk-len configuration parameter to a very large value and constructing specially crafted network payloads or commands. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the proto-max- bulk-len configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command. (CVE-2021-41099)
Note that Nessus has not tested for these issues but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALASREDIS6-2023-007.
##
include('compat.inc');
if (description)
{
script_id(182071);
script_version("1.0");
script_set_attribute(attribute:"plugin_modification_date", value:"2023/09/27");
script_cve_id(
"CVE-2021-32626",
"CVE-2021-32627",
"CVE-2021-32628",
"CVE-2021-32672",
"CVE-2021-32675",
"CVE-2021-32762",
"CVE-2021-41099"
);
script_name(english:"Amazon Linux 2 : redis (ALASREDIS6-2023-007)");
script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
script_set_attribute(attribute:"description", value:
"The version of redis installed on the remote host is prior to 6.2.6-1. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2REDIS6-2023-007 advisory.
- Redis is an open source, in-memory database that persists on disk. In affected versions specially crafted
Lua scripts executing in Redis can cause the heap-based Lua stack to be overflowed, due to incomplete
checks for this condition. This can result with heap corruption and potentially remote code execution.
This problem exists in all versions of Redis with Lua scripting support, starting from 2.6. The problem is
fixed in versions 6.2.6, 6.0.16 and 5.0.14. For users unable to update an additional workaround to
mitigate the problem without patching the redis-server executable is to prevent users from executing Lua
scripts. This can be done using ACL to restrict EVAL and EVALSHA commands. (CVE-2021-32626)
- Redis is an open source, in-memory database that persists on disk. In affected versions an integer
overflow bug in Redis can be exploited to corrupt the heap and potentially result with remote code
execution. The vulnerability involves changing the default proto-max-bulk-len and client-query-buffer-
limit configuration parameters to very large values and constructing specially crafted very large stream
elements. The problem is fixed in Redis 6.2.6, 6.0.16 and 5.0.14. For users unable to upgrade an
additional workaround to mitigate the problem without patching the redis-server executable is to prevent
users from modifying the proto-max-bulk-len configuration parameter. This can be done using ACL to
restrict unprivileged users from using the CONFIG SET command. (CVE-2021-32627)
- Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the ziplist
data structure used by all versions of Redis can be exploited to corrupt the heap and potentially result
with remote code execution. The vulnerability involves modifying the default ziplist configuration
parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max-
ziplist-value) to a very large value, and then constructing specially crafted commands to create very
large ziplists. The problem is fixed in Redis versions 6.2.6, 6.0.16, 5.0.14. An additional workaround to
mitigate the problem without patching the redis-server executable is to prevent users from modifying the
above configuration parameters. This can be done using ACL to restrict unprivileged users from using the
CONFIG SET command. (CVE-2021-32628)
- Redis is an open source, in-memory database that persists on disk. When using the Redis Lua Debugger,
users can send malformed requests that cause the debugger's protocol parser to read data beyond the actual
buffer. This issue affects all versions of Redis with Lua debugging support (3.2 or newer). The problem is
fixed in versions 6.2.6, 6.0.16 and 5.0.14. (CVE-2021-32672)
- 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.
(CVE-2021-32675)
- 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.
(CVE-2021-32762)
- Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the
underlying string library can be used to corrupt the heap and potentially result with denial of service or
remote code execution. The vulnerability involves changing the default proto-max-bulk-len configuration
parameter to a very large value and constructing specially crafted network payloads or commands. The
problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate the
problem without patching the redis-server executable is to prevent users from modifying the proto-max-
bulk-len configuration parameter. This can be done using ACL to restrict unprivileged users from using the
CONFIG SET command. (CVE-2021-41099)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/AL2/ALASREDIS6-2023-007.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32626.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32627.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32628.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32672.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32675.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-32762.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-41099.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
script_set_attribute(attribute:"solution", value:
"Run 'yum update redis' to update your system.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-32762");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"vuln_publication_date", value:"2021/10/04");
script_set_attribute(attribute:"patch_publication_date", value:"2023/08/21");
script_set_attribute(attribute:"plugin_publication_date", value:"2023/09/27");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:redis");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:redis-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:redis-devel");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:redis-doc");
script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Amazon Linux Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2023 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");
exit(0);
}
include("rpm.inc");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "2")
{
if (os_ver == 'A') os_ver = 'AMI';
audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}
if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
var pkgs = [
{'reference':'redis-6.2.6-1.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-6.2.6-1.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-debuginfo-6.2.6-1.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-debuginfo-6.2.6-1.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-devel-6.2.6-1.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-devel-6.2.6-1.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'},
{'reference':'redis-doc-6.2.6-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'redis6'}
];
var flag = 0;
foreach var package_array ( pkgs ) {
var reference = NULL;
var _release = NULL;
var sp = NULL;
var _cpu = NULL;
var el_string = NULL;
var rpm_spec_vers_cmp = NULL;
var epoch = NULL;
var allowmaj = NULL;
var exists_check = NULL;
if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
if (!empty_or_null(package_array['release'])) _release = package_array['release'];
if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
}
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_HOLE,
extra : rpm_report_get()
);
exit(0);
}
else
{
var tested = pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, "redis / redis-debuginfo / redis-devel / etc");
}
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32626
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32627
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32628
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32672
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32675
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-32762
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-41099
alas.aws.amazon.com/AL2/ALASREDIS6-2023-007.html
alas.aws.amazon.com/cve/html/CVE-2021-32626.html
alas.aws.amazon.com/cve/html/CVE-2021-32627.html
alas.aws.amazon.com/cve/html/CVE-2021-32628.html
alas.aws.amazon.com/cve/html/CVE-2021-32672.html
alas.aws.amazon.com/cve/html/CVE-2021-32675.html
alas.aws.amazon.com/cve/html/CVE-2021-32762.html
alas.aws.amazon.com/cve/html/CVE-2021-41099.html
alas.aws.amazon.com/faqs.html