CWE-22 (对路径名的限制不恰当(路径遍历)) — Vulnerability Class 5197

5197 vulnerabilities classified as CWE-22 (对路径名的限制不恰当(路径遍历)). AI Chinese analysis included.

CWE-22 represents a critical input validation weakness where software fails to properly sanitize external input before constructing file paths. Attackers typically exploit this vulnerability by injecting directory traversal sequences, such as “../”, into user-supplied parameters. These malicious inputs allow the application to resolve file references outside the intended restricted directory, potentially granting unauthorized access to sensitive system files, configuration data, or source code. To mitigate this risk, developers must implement rigorous input validation techniques, ensuring that all path components are strictly checked against allowed characters and structures. Additionally, employing canonicalization to resolve symbolic links and relative paths before validation, combined with strict chroot jails or sandboxing, effectively confines file operations to designated directories, thereby neutralizing the potential for path traversal attacks and preserving system integrity.

MITRE CWE Description

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Many file operations are intended to take place within a restricted directory. By using special elements such as ".." and "/" separators, attackers can escape outside of the restricted location to access files or directories that are elsewhere on the system. One of the most common special elements is the "../" sequence, which in most modern operating systems is interpreted as the parent directory of the current location. This is referred to as relative path traversal. Path traversal also covers the use of absolute pathnames such as "/usr/local/bin" to access unexpected files. This is referred to as absolute path traversal.

Common Consequences (4)

Integrity, Confidentiality, Availability Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow …

Confidentiality Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing a…

Availability DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.

Mitigations (5)

Implementation Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range…

Architecture and Design For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Implementation Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked. Use a built-in path canonicalization function (such as realpath(…

Architecture and Design Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].

Operation Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].

Effectiveness: Moderate

Examples (2)

The following code could be for a social networking application in which each user's profile information is stored in a separate file. All files are stored in a single directory.

my $dataPath = "/users/cwe/profiles"; my $username = param("user"); my $profilePath = $dataPath . "/" . $username; open(my $fh, "<", $profilePath) || ExitError("profile read error: $profilePath"); print "<ul>\n"; while (<$fh>) { print "<li>$_</li>\n"; } print "</ul>\n";

Bad · Perl

../../../etc/passwd

Attack

In the example below, the path to a dictionary file is read from a system property and used to initialize a File object.

String filename = System.getProperty("com.domain.application.dictionaryFile"); File dictionaryFile = new File(filename);

Bad · Java

CVE ID	Title	CVSS	Severity	Published
CVE-2021-27276	NETGEAR ProSAFE Network Management System 路径遍历漏洞 — ProSAFE Network Management System	7.1	-	2021-03-29
CVE-2021-27275	NETGEAR ProSAFE Network Management System 路径遍历漏洞 — ProSAFE Network Management System	8.3	-	2021-03-29
CVE-2021-27272	NETGEAR ProSAFE Network Management System 路径遍历漏洞 — ProSAFE Network Management System	7.1	-	2021-03-29
CVE-2021-25367	Samsung Notes 路径遍历漏洞 — Samsung Notes	3.7	Low	2021-03-25
CVE-2020-26279	Path traversal — go-ipfs	7.7	High	2021-03-24
CVE-2021-1385	Cisco IOx Application Environment Path Traversal Vulnerability — Cisco IOS	6.5	Medium	2021-03-24
CVE-2021-1436	Cisco IOS XE SD-WAN Software Path Traversal Vulnerability — Cisco IOS XE Software	4.4	Medium	2021-03-24
CVE-2021-1435	Cisco IOS XE Software Web UI Command Injection Vulnerability — Cisco IOS XE Software	8.8	-	2021-03-24
CVE-2021-21402	Unauthenticated Arbitrary File Access in Jellyfin — jellyfin	7.7	High	2021-03-23
CVE-2021-20218	Rohan Kumar kubernetes-client 路径遍历漏洞 — fabric8-kubernetes-client	5.9	-	2021-03-16
CVE-2021-21514	Dell EMC OpenManage Server Administrator 路径遍历漏洞 — Dell Open Manage Server Administrator	4.9	Medium	2021-03-02
CVE-2021-21298	Path traversal in Node-Red — node-red	3.5	Low	2021-02-26
CVE-2021-21064	Magento UPWARD-php Path traversal vulnerability via UPWARD Connector — Magento Commerce	4.9	-	2021-02-25
CVE-2021-22651	Luxion KeyShot 路径遍历漏洞 — Luxion KeyShot versions	7.1	-	2021-02-23
CVE-2020-13550	Advantech WebAccess/SCADA 路径遍历漏洞 — Advantech	7.7	-	2021-02-17
CVE-2021-22857	ChanGate EnterPrise Co., Ltd property management system - Directory Traversal — property management system	7.5	High	2021-02-17
CVE-2020-29026	Secomea GateManager 路径遍历漏洞 — GateManager	9.0	Critical	2021-02-15
CVE-2021-21037	Acrobat Reader DC Path Traversal Vulnerability Could Lead To Arbitrary Code Execution — Acrobat Reader	7.8	High	2021-02-11
CVE-2021-22656	Advantech Iview 路径遍历漏洞 — Advantech iView	7.5	-	2021-02-11
CVE-2020-27871	Solarwinds SolarWinds Orion Platform 路径遍历漏洞 — Orion Platform	8.8	-	2021-02-10
CVE-2020-27870	Solarwinds SolarWinds Orion Platform 路径遍历漏洞 — Orion Platform	6.5	-	2021-02-10
CVE-2020-26299	File System Bounds Escape — ftp-srv	6.3	Medium	2021-02-10
CVE-2020-25237	SINEC NMS 路径遍历漏洞 — SINEC NMS	8.1	-	2021-02-09
CVE-2021-21284	privilege escalation in Moby — moby	6.8	Medium	2021-02-02
CVE-2020-15097	Path Traversal in loklak — loklak	9.1	Critical	2021-02-02
CVE-2021-21272	zip slip in ORAS — oras	7.7	High	2021-01-25
CVE-2020-26295	CMS Editor code execution — magento-lts	8.7	High	2021-01-21
CVE-2020-26285	Widget instances allows a hacker to inject an executable file on the server on OpenMage — magento-lts	8.7	High	2021-01-21
CVE-2020-26252	Layout XML RCE Vulnerability in OpenMage — magento-lts	8.7	High	2021-01-20
CVE-2021-1259	Cisco SD-WAN vManage Software Path Traversal Vulnerability — Cisco SD-WAN vManage	6.5	-	2021-01-20

Vulnerabilities classified as CWE-22 (对路径名的限制不恰当(路径遍历)) represent 5197 CVEs. The CWE taxonomy describes the weakness; review individual CVEs for product-specific impact.