CWE-154
Improper Neutralization of Variable Name Delimiters
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as variable name delimiters when they are sent to a downstream component.
CVE-2024-39698 (GCVE-0-2024-39698)
Vulnerability from cvelistv5
Published
2024-07-09 17:50
Modified
2024-08-02 04:26
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-154 - Improper Neutralization of Variable Name Delimiters
Summary
electron-updater allows for automatic updates for Electron apps. The file `packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts` implements the signature validation routine for Electron applications on Windows. Because of the surrounding shell, a first pass by `cmd.exe` expands any environment variable found in command-line above. This creates a situation where `verifySignature()` can be tricked into validating the certificate of a different file than the one that was just downloaded. If the step is successful, the malicious update will be executed even if its signature is invalid. This attack assumes a compromised update manifest (server compromise, Man-in-the-Middle attack if fetched over HTTP, Cross-Site Scripting to point the application to a malicious updater server, etc.). The patch is available starting from 6.3.0-alpha.6.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| electron-userland | electron-builder |
Version: < 6.3.0-alpha.6 |
{
"containers": {
"adp": [
{
"affected": [
{
"cpes": [
"cpe:2.3:a:electron:electron:*:*:*:*:*:*:*:*"
],
"defaultStatus": "unknown",
"product": "electron",
"vendor": "electron",
"versions": [
{
"lessThan": "6.3.0-alpha.6",
"status": "affected",
"version": "0",
"versionType": "custom"
}
]
}
],
"metrics": [
{
"other": {
"content": {
"id": "CVE-2024-39698",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-07-10T14:40:10.938790Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2024-07-10T14:41:06.824Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
},
{
"providerMetadata": {
"dateUpdated": "2024-08-02T04:26:15.985Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"name": "https://github.com/electron-userland/electron-builder/security/advisories/GHSA-9jxc-qjr9-vjxq",
"tags": [
"x_refsource_CONFIRM",
"x_transferred"
],
"url": "https://github.com/electron-userland/electron-builder/security/advisories/GHSA-9jxc-qjr9-vjxq"
},
{
"name": "https://github.com/electron-userland/electron-builder/pull/8295",
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://github.com/electron-userland/electron-builder/pull/8295"
},
{
"name": "https://github.com/electron-userland/electron-builder/commit/ac2e6a25aa491c1ef5167a552c19fc2085cd427f",
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://github.com/electron-userland/electron-builder/commit/ac2e6a25aa491c1ef5167a552c19fc2085cd427f"
},
{
"name": "https://github.com/electron-userland/electron-builder/blob/140e2f0eb0df79c2a46e35024e96d0563355fc89/packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts#L35-L41",
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://github.com/electron-userland/electron-builder/blob/140e2f0eb0df79c2a46e35024e96d0563355fc89/packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts#L35-L41"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"product": "electron-builder",
"vendor": "electron-userland",
"versions": [
{
"status": "affected",
"version": "\u003c 6.3.0-alpha.6"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "electron-updater allows for automatic updates for Electron apps. The file `packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts` implements the signature validation routine for Electron applications on Windows. Because of the surrounding shell, a first pass by `cmd.exe` expands any environment variable found in command-line above. This creates a situation where `verifySignature()` can be tricked into validating the certificate of a different file than the one that was just downloaded. If the step is successful, the malicious update will be executed even if its signature is invalid. This attack assumes a compromised update manifest (server compromise, Man-in-the-Middle attack if fetched over HTTP, Cross-Site Scripting to point the application to a malicious updater server, etc.). The patch is available starting from 6.3.0-alpha.6."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-154",
"description": "CWE-154: Improper Neutralization of Variable Name Delimiters",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2024-07-09T17:50:28.169Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/electron-userland/electron-builder/security/advisories/GHSA-9jxc-qjr9-vjxq",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/electron-userland/electron-builder/security/advisories/GHSA-9jxc-qjr9-vjxq"
},
{
"name": "https://github.com/electron-userland/electron-builder/pull/8295",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/electron-userland/electron-builder/pull/8295"
},
{
"name": "https://github.com/electron-userland/electron-builder/commit/ac2e6a25aa491c1ef5167a552c19fc2085cd427f",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/electron-userland/electron-builder/commit/ac2e6a25aa491c1ef5167a552c19fc2085cd427f"
},
{
"name": "https://github.com/electron-userland/electron-builder/blob/140e2f0eb0df79c2a46e35024e96d0563355fc89/packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts#L35-L41",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/electron-userland/electron-builder/blob/140e2f0eb0df79c2a46e35024e96d0563355fc89/packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts#L35-L41"
}
],
"source": {
"advisory": "GHSA-9jxc-qjr9-vjxq",
"discovery": "UNKNOWN"
},
"title": "Code Signing Bypass on Windows in electron-updater \u003c 6.3.0-alpha.6"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2024-39698",
"datePublished": "2024-07-09T17:50:28.169Z",
"dateReserved": "2024-06-27T18:44:13.037Z",
"dateUpdated": "2024-08-02T04:26:15.985Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
Mitigation
Phases:
Description:
- Developers should anticipate that variable name delimiters will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
Mitigation ID: MIT-5
Phase: Implementation
Strategy: Input Validation
Description:
- 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 of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
Mitigation ID: MIT-28
Phase: Implementation
Strategy: Output Encoding
Description:
- While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments. The most conservative approach is to escape or filter all characters that do not pass an extremely strict allowlist (such as everything that is not alphanumeric or white space). If some special characters are still needed, such as white space, wrap each argument in quotes after the escaping/filtering step. Be careful of argument injection (CWE-88).
Mitigation ID: MIT-20
Phase: Implementation
Strategy: Input Validation
Description:
- 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.
CAPEC-15: Command Delimiters
An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or denylist input validation, as opposed to allowlist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or denylist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.