CVE-2021-37701
mediumpriority · track · 35EPSS 0.033 · 88 %ileDEEURUUSEPSS · scored 2026-10-27
The npm package "tar" (aka node-tar) before versions 4.4.16, 5.0.8, and 6.1.7 has an arbitrary file creation/overwrite and arbitrary code execution vulnerability. node-tar aims to guarantee that any file whose location would be modified by a symbolic link is not extracted. This is, in part, achieved by ensuring that extracted directories are not symlinks. Additionally, in order to prevent unnecessary stat calls to determine whether a given path is a directory, paths are cached when directories are created. This logic was insufficient when extracting tar files that contained both a directory and a symlink with the same name as the directory, where the symlink and directory names in the archive entry used backslashes as a path separator on posix systems. The cache checking logic used both `\` and `/` characters as path separators, however `\` is a valid filename character on posix systems. By first creating a directory, and then replacing that directory with a symlink, it was thus possible to bypass node-tar symlink checks on directories, essentially allowing an untrusted tar file to symlink into an arbitrary location and subsequently extracting arbitrary files into that location, thus allowing arbitrary file creation and overwrite. Additionally, a similar confusion could arise on case-insensitive filesystems. If a tar archive contained a directory at `FOO`, followed by a symbolic link named `foo`, then on case-insensitive file systems, the creation of the symbolic link would remove the directory from the filesystem, but _not_ from the internal directory cache, as it would not be treated as a cache hit. A subsequent file entry within the `FOO` directory would then be placed in the target of the symbolic link, thinking that the directory had already been created. These issues were addressed in releases 4.4.16, 5.0.8 and 6.1.7. The v3 branch of node-tar has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of node-tar. If this is not possible, a workaround is available in the referenced GHSA-9r2w-394v-53qc.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixedfesto_psirt
FactoryViews (non-Lite): Upgrade to FactoryViews 1.6.0. See the upgrade guide for information on how to upgrade. FactoryViews Lite: Upgrade to FactoryViews 1.7.0. See the upgrade guide for information on how to upgrade.
- FixedSINEC INSsiemens_psirt
Update to V1.0.1.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109806100/ - FixedSINEC INScisa_csaf_ot
Update to V1.0.1.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109806100/
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 · 4.4–8.6
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (38)
Products and version ranges known to be affected.
- FactoryViews 1.6.0all versionsfixedfesto_psirtDEcpe:2.3:a:festo:factory_views_software:1.6.0:*:*:*:*:*:*:*
- FactoryViews 1.7.0all versionsfixedfesto_psirtDEcpe:2.3:a:festo:factory_views_software:1.7.0:*:*:*:*:*:*:*
advisories (10)
Vendor and ecosystem advisories describing this.
- FSA-202302Festo: Several vulnerabilities in FactoryViews2023-07-10csaf · festo_psirtDE
FactoryViews bundles many third-party applications which are used in background processes to provide the software's features. From time to time, vulnerabilities in these bundled applications are discovered. These are typically fixed in newer versions of FactoryViews by updating the bundled applications. FactoryViews versions up to and including 1.5.2 contain around 200 such vulnerabilities listed in this advisory.Version 1.6.0 is a security rollup release which includes updates to all bundled applications and fixes these vulnerabilities. At this time, FactoryViews Lite cannot be updated beyond version 1.1. FactoryViews 1.7 unifies the non-Lite and Lite versions and fixes these vulnerabilities for users of FactoryViews Lite.
- SSA-389290SSA-389290: Third-Party Component Vulnerabilities in SINEC INS2022-03-08csaf · siemens_psirtDE
71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.
- WID-SEC-W-2022-0092Node.js: Mehrere Schwachstellen ermöglichen Manipulation von DateienDeutsch2021-08-31csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Node.js ausnutzen, um Dateien zu manipulieren.
- WID-SEC-W-2022-1603IBM Tivoli Netcool/OMNIbus: Mehrere SchwachstellenDeutsch2022-10-03csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM Tivoli Netcool/OMNIbus ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen, Dateien zu manipulieren oder einen Denial of Service Zustand herbeizuführen.
- WID-SEC-W-2023-0809IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2023-03-30csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen, Informationen falsch darzustellen, einen Denial of Service Zustand herbeizuführen, Sicherheitsvorkehrungen zu umgehen, einen Cross-Site-Scripting-Angriff durchzuführen oder unbekannte Auswirkungen zu verursachen.
- WID-SEC-W-2023-0856IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2022-05-31csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
- WID-SEC-W-2023-0857IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2022-05-24csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Programmcode auszuführen, einen Denial of Service Zustand herbeizuführen, Dateien manipulieren oder Sicherheitsvorkehrungen zu umgehen.
- WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.
- GHSA-9r2w-394v-53qcArbitrary File Creation/Overwrite via insufficient symlink protection due to directory cache poisoning using symbolic links2021-08-31ghsa · osvUS
### Impact Arbitrary File Creation, Arbitrary File Overwrite, Arbitrary Code Execution `node-tar` aims to guarantee that any file whose location would be modified by a symbolic link is not extracted. This is, in part, achieved by ensuring that extracted directories are not symlinks. Additionally, in order to prevent unnecessary stat calls to determine whether a given path is a directory, paths are cached when directories are created. This logic was insufficient when extracting tar files that contained both a directory and a symlink with the same name as the directory, where the symlink and directory names in the archive entry used backslashes as a path separator on posix systems. The cache checking logic used both `\` and `/` characters as path separators, however `\` is a valid filename character on posix systems. By first creating a directory, and then replacing that directory with a symlink, it was thus possible to bypass node-tar symlink checks on directories, essentially allowing an untrusted tar file to symlink into an arbitrary location and subsequently extracting arbitrary files into that location, thus allowing arbitrary file creation and overwrite. Additionally, a similar confusion could arise on case-insensitive filesystems. If a tar archive contained a directory at `FOO`, followed by a symbolic link named `foo`, then on case-insensitive file systems, the creation of the symbolic link would remove the directory from the filesystem, but _not_ from the internal directory cache, as it would not be treated as a cache hit. A subsequent file entry within the `FOO` directory would then be placed in the target of the symbolic link, thinking that the directory had already been created. These issues were addressed in releases 4.4.16, 5.0.8 and 6.1.7. The v3 branch of `node-tar` has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of `node-tar`. If this is not possible, a workaround is available below. ### Patches 4.4.16 || 5.0.8 || 6.1.7 ### Workarounds Users may work around this vulnerability without upgrading by creating a custom filter method which prevents the extraction of symbolic links. ```js const tar = require('tar') tar.x({ file: 'archive.tgz', filter: (file, entry) => { if (entry.type === 'SymbolicLink') { return false } else { return true } } }) ``` Users are encouraged to upgrade to the latest patched versions, rather than attempt to sanitize tar input themselves. ### Fix The problem is addressed in the following ways: 1. All paths are normalized to use `/` as a path separator, replacing `\` with `/` on Windows systems, and leaving `\` intact in the path on posix systems. This is performed in depth, at every level of the program where paths are consumed. 2. Directory cache pruning is performed case-insensitively. This _may_ result in undue cache misses on case-sensitive file systems, but the performance impact is negligible. #### Caveat Note that this means that the `entry` objects exposed in various parts of tar's API will now always use `/` as a path separator, even on Windows systems. This is not expected to cause problems, as `/` is a valid path separator on Windows systems, but _may_ result in issues if `entry.path` is compared against a path string coming from some other API such as `fs.realpath()` or `path.resolve()`. Users are encouraged to always normalize paths using a well-tested method such as `path.resolve()` before comparing paths to one another.
- ICSA-22-069-09Siemens SINEC INS2022-03-08icsa · cisa_csaf_otUS
71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (45)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2021-37701cnnvd
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdfcnnvd
- https://github.com/npm/node-tar/security/advisories/GHSA-9r2w-394v-53qccnnvd
- https://lists.debian.org/debian-lts-announce/2022/12/msg00023.htmlcnnvd
- https://packetstormsecurity.com/files/165275/Red-Hat-Security-Advisory-2021-5086-06.htmlcnnvd
- https://packetstormsecurity.com/files/165485/Red-Hat-Security-Advisory-2022-0041-02.htmlcnnvd
- https://packetstormsecurity.com/files/165705/Red-Hat-Security-Advisory-2022-0246-04.htmlcnnvd
- https://packetstormsecurity.com/files/165815/Red-Hat-Security-Advisory-2022-0350-04.htmlcnnvd
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