CWE-502
AllowedDeserialization of Untrusted Data
Abstraction: Base · Status: Draft
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
4812 vulnerabilities reference this CWE, most recent first.
GHSA-PQQW-32FF-9FW8
Vulnerability from github – Published: 2025-12-18 09:30 – Updated: 2026-01-20 15:32Deserialization of Untrusted Data vulnerability in CRM Perks WP Gravity Forms Constant Contact Plugin gf-constant-contact allows Object Injection.This issue affects WP Gravity Forms Constant Contact Plugin: from n/a through <= 1.1.2.
{
"affected": [],
"aliases": [
"CVE-2025-60174"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-18T08:16:09Z",
"severity": "CRITICAL"
},
"details": "Deserialization of Untrusted Data vulnerability in CRM Perks WP Gravity Forms Constant Contact Plugin gf-constant-contact allows Object Injection.This issue affects WP Gravity Forms Constant Contact Plugin: from n/a through \u003c= 1.1.2.",
"id": "GHSA-pqqw-32ff-9fw8",
"modified": "2026-01-20T15:32:30Z",
"published": "2025-12-18T09:30:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-60174"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/Wordpress/Plugin/gf-constant-contact/vulnerability/wordpress-wp-gravity-forms-constant-contact-plugin-plugin-1-1-2-deserialization-of-untrusted-data-vulnerability?_s_id=cve"
},
{
"type": "WEB",
"url": "https://vdp.patchstack.com/database/Wordpress/Plugin/gf-constant-contact/vulnerability/wordpress-wp-gravity-forms-constant-contact-plugin-plugin-1-1-2-deserialization-of-untrusted-data-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PQVF-2W8F-4R2Q
Vulnerability from github – Published: 2023-07-24 18:30 – Updated: 2024-04-04 06:20A vulnerability exists by allowing low-privileged users to read and update the data in various directories used by the Zenon system. An attacker could exploit the vulnerability by using specially crafted programs to exploit the vulnerabilities by allowing them to run on the zenon installed hosts. This issue affects ABB Ability™ zenon: from 11 build through 11 build 106404.
{
"affected": [],
"aliases": [
"CVE-2023-3324"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-07-24T18:15:23Z",
"severity": "HIGH"
},
"details": "\nA vulnerability exists by allowing low-privileged users to read and update the data in various directories used by the Zenon system. An attacker could exploit the vulnerability by using specially crafted\nprograms to exploit the vulnerabilities by allowing them to run on the zenon installed hosts.\nThis issue affects ABB Ability\u2122 zenon: from 11 build through 11 build 106404.\n\n\n\n",
"id": "GHSA-pqvf-2w8f-4r2q",
"modified": "2024-04-04T06:20:27Z",
"published": "2023-07-24T18:30:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-3324"
},
{
"type": "WEB",
"url": "https://search.abb.com/library/Download.aspx?DocumentID=2NGA001801\u0026LanguageCode=en\u0026DocumentPartId=\u0026Action=Launch\u0026_ga=2.194142766.2067879716.1690216773-1911411808.1686627590"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PQWH-C2F3-VXMQ
Vulnerability from github – Published: 2023-06-09 19:31 – Updated: 2023-06-09 19:31Impact
A bug in the Data.init(base32Encoded:) function opens up the potential for exposing server memory and/or crashing the server (Denial of Service) for applications where untrusted data can end up in said function. Vapor does not currently use this function itself so this only impact applications that use the impacted function directly or through other dependencies.
Patches
This issue has been patched in 4.47.2.
Workarounds
Use an alternative to Vapor's built-in Data.init(base32Encoded:).
For more information
If you have any questions or comments about this advisory: * Open an issue in Vapor * Ask in Discord
{
"affected": [
{
"package": {
"ecosystem": "SwiftURL",
"name": "github.com/vapor/vapor"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "4.47.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-32742"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": true,
"github_reviewed_at": "2023-06-09T19:31:54Z",
"nvd_published_at": "2021-07-09T14:15:00Z",
"severity": "MODERATE"
},
"details": "### Impact\nA bug in the `Data.init(base32Encoded:)` function opens up the potential for exposing server memory and/or crashing the server (Denial of Service) for applications where untrusted data can end up in said function. Vapor does not currently use this function itself so this only impact applications that use the impacted function directly or through other dependencies.\n\n### Patches\nThis issue has been patched in 4.47.2.\n\n### Workarounds\nUse an alternative to Vapor\u0027s built-in `Data.init(base32Encoded:)`.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue in [Vapor](https://github.com/vapor/vapor)\n* Ask in [Discord](http://vapor.team)",
"id": "GHSA-pqwh-c2f3-vxmq",
"modified": "2023-06-09T19:31:54Z",
"published": "2023-06-09T19:31:54Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/vapor/vapor/security/advisories/GHSA-pqwh-c2f3-vxmq"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32742"
},
{
"type": "PACKAGE",
"url": "https://github.com/vapor/vapor"
},
{
"type": "WEB",
"url": "https://github.com/vapor/vapor/releases/tag/4.47.2"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Untrusted data fed into `Data.init(base32Encoded:)` can result in exposing server memory and/or crash"
}
GHSA-PQWP-HQ22-PR35
Vulnerability from github – Published: 2025-12-18 09:30 – Updated: 2026-01-20 15:32Deserialization of Untrusted Data vulnerability in magepeopleteam Booking and Rental Manager booking-and-rental-manager-for-woocommerce allows Object Injection.This issue affects Booking and Rental Manager: from n/a through <= 2.5.4.
{
"affected": [],
"aliases": [
"CVE-2025-64266"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-18T08:16:13Z",
"severity": "HIGH"
},
"details": "Deserialization of Untrusted Data vulnerability in magepeopleteam Booking and Rental Manager booking-and-rental-manager-for-woocommerce allows Object Injection.This issue affects Booking and Rental Manager: from n/a through \u003c= 2.5.4.",
"id": "GHSA-pqwp-hq22-pr35",
"modified": "2026-01-20T15:32:31Z",
"published": "2025-12-18T09:30:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-64266"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/Wordpress/Plugin/booking-and-rental-manager-for-woocommerce/vulnerability/wordpress-booking-and-rental-manager-plugin-2-5-4-php-object-injection-vulnerability?_s_id=cve"
},
{
"type": "WEB",
"url": "https://vdp.patchstack.com/database/Wordpress/Plugin/booking-and-rental-manager-for-woocommerce/vulnerability/wordpress-booking-and-rental-manager-plugin-2-5-4-php-object-injection-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PQXV-Q4C6-WH8Q
Vulnerability from github – Published: 2026-07-04 03:31 – Updated: 2026-07-04 03:31picklescan before 0.0.33 fails to detect malicious pickle files using numpy.f2py.crackfortran.param_eval function in reduce methods, allowing attackers to bypass security checks. Remote attackers can embed undetected code in pickle files that executes during deserialization, enabling arbitrary code execution in applications loading untrusted pickle data.
{
"affected": [],
"aliases": [
"CVE-2025-71347"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-04T02:16:21Z",
"severity": "HIGH"
},
"details": "picklescan before 0.0.33 fails to detect malicious pickle files using numpy.f2py.crackfortran.param_eval function in reduce methods, allowing attackers to bypass security checks. Remote attackers can embed undetected code in pickle files that executes during deserialization, enabling arbitrary code execution in applications loading untrusted pickle data.",
"id": "GHSA-pqxv-q4c6-wh8q",
"modified": "2026-07-04T03:31:01Z",
"published": "2026-07-04T03:31:01Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/mmaitre314/picklescan/security/advisories/GHSA-cffc-mxrf-mhh4"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-71347"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/picklescan-undetected-remote-code-execution-via-numpy-f2py-crackfortran-param-eval"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-PR3P-9QH5-QP2F
Vulnerability from github – Published: 2025-05-23 15:31 – Updated: 2026-04-01 18:35Deserialization of Untrusted Data vulnerability in AncoraThemes Jarvis – Night Club, Concert, Festival WordPress allows Object Injection. This issue affects Jarvis – Night Club, Concert, Festival WordPress: from n/a through 1.8.11.
{
"affected": [],
"aliases": [
"CVE-2025-32292"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-05-23T13:15:29Z",
"severity": "CRITICAL"
},
"details": "Deserialization of Untrusted Data vulnerability in AncoraThemes Jarvis \u2013 Night Club, Concert, Festival WordPress allows Object Injection. This issue affects Jarvis \u2013 Night Club, Concert, Festival WordPress: from n/a through 1.8.11.",
"id": "GHSA-pr3p-9qh5-qp2f",
"modified": "2026-04-01T18:35:14Z",
"published": "2025-05-23T15:31:10Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-32292"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/wordpress/theme/jarvis/vulnerability/wordpress-jarvis-night-club-concert-festival-wordpress-1-8-11-php-object-injection-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PR9J-P6WX-P73X
Vulnerability from github – Published: 2024-03-28 06:30 – Updated: 2026-04-01 18:31Deserialization of Untrusted Data vulnerability in WP Sunshine Sunshine Photo Cart.This issue affects Sunshine Photo Cart: from n/a through 3.1.1.
{
"affected": [],
"aliases": [
"CVE-2024-30221"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-03-28T06:15:14Z",
"severity": "MODERATE"
},
"details": "Deserialization of Untrusted Data vulnerability in WP Sunshine Sunshine Photo Cart.This issue affects Sunshine Photo Cart: from n/a through 3.1.1.",
"id": "GHSA-pr9j-p6wx-p73x",
"modified": "2026-04-01T18:31:43Z",
"published": "2024-03-28T06:30:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-30221"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/Wordpress/Plugin/sunshine-photo-cart/vulnerability/wordpress-sunshine-photo-cart-plugin-3-1-1-php-object-injection-vulnerability?_s_id=cve"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/vulnerability/sunshine-photo-cart/wordpress-sunshine-photo-cart-plugin-3-1-1-php-object-injection-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-PRF8-CF2X-RHX7
Vulnerability from github – Published: 2026-04-29 20:41 – Updated: 2026-05-20 22:56Summary
This advisory covers the deprecated fabric-sdk-java client SDK. Channel.java implements readObject() and exposes deSerializeChannel() which call ObjectInputStream.readObject() on untrusted byte arrays without configuring an ObjectInputFilter. This is the classic Java deserialization RCE pattern.
Note: fabric-sdk-java is deprecated and maintained in https://github.com/hyperledger/fabric-sdk-java. Filing here as that repo does not have private vulnerability reporting enabled.
Affected Code
// src/main/java/org/hyperledger/fabric/sdk/Channel.java
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject(); // No ObjectInputFilter configured
}
public Channel deSerializeChannel(byte[] channelBytes)
throws IOException, ClassNotFoundException, InvalidArgumentException {
ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(channelBytes));
Channel channel = (Channel) ois.readObject(); // Untrusted bytes deserialized
return channel;
}
Attack Vector
An attacker who can supply crafted serialized Channel bytes to the client application — for example, by compromising a local channel file, injecting data through an application that accepts Channel bytes from external sources, or exploiting a separate write primitive — can achieve RCE via gadget chain exploitation when deSerializeChannel() processes those bytes. The risk is highest in deployments that accept Channel data from sources outside the client's direct control. Note: channel data is not transmitted from Fabric peers; this is a client-side deserialization surface.
Proof of Concept
// Generate malicious payload with ysoserial:
// java -jar ysoserial.jar CommonsCollections6 "touch /tmp/pwned" > malicious_channel.ser
// Victim code:
byte[] maliciousBytes = Files.readAllBytes(Paths.get("malicious_channel.ser"));
Channel channel = client.deSerializeChannel(maliciousBytes); // RCE fires here
Notes on Deprecation
fabric-sdk-java is deprecated as of Hyperledger Fabric v2.5 (replaced by org.hyperledger.fabric:fabric-gateway). However, organizations that have not yet migrated remain fully exposed. Automated dependency scanners (Snyk, Dependabot) cannot alert users without a published GHSA. This advisory is filed to ensure those users are notified and directed to migrate.
Fix
For the deprecated SDK: add ObjectInputFilter to whitelist only expected classes:
ObjectInputFilter filter = ObjectInputFilter.Config.createFilter(
"org.hyperledger.fabric.sdk.*;java.util.*;java.lang.*;!*"
);
ois.setObjectInputFilter(filter);
The recommended remediation is migration to org.hyperledger.fabric:fabric-gateway, which does not use Java serialization.
Resources
- CWE-502: Deserialization of Untrusted Data
- Migration guide: https://hyperledger.github.io/fabric-gateway/
Credits
Found by Martin Brodeur (brodmart) via independent security research.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.hyperledger.fabric-sdk-java:fabric-sdk-java"
},
"ranges": [
{
"events": [
{
"introduced": "1.0.0"
},
{
"last_affected": "2.2.26"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-41586"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-29T20:41:58Z",
"nvd_published_at": "2026-05-07T06:16:04Z",
"severity": "CRITICAL"
},
"details": "## Summary\n\nThis advisory covers the deprecated `fabric-sdk-java` client SDK. `Channel.java` implements `readObject()` and exposes `deSerializeChannel()` which call `ObjectInputStream.readObject()` on untrusted byte arrays without configuring an `ObjectInputFilter`. This is the classic Java deserialization RCE pattern.\n\n**Note:** `fabric-sdk-java` is deprecated and maintained in https://github.com/hyperledger/fabric-sdk-java. Filing here as that repo does not have private vulnerability reporting enabled.\n\n## Affected Code\n\n```java\n// src/main/java/org/hyperledger/fabric/sdk/Channel.java\nprivate void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {\n in.defaultReadObject(); // No ObjectInputFilter configured\n}\n\npublic Channel deSerializeChannel(byte[] channelBytes)\n throws IOException, ClassNotFoundException, InvalidArgumentException {\n ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(channelBytes));\n Channel channel = (Channel) ois.readObject(); // Untrusted bytes deserialized\n return channel;\n}\n```\n\n## Attack Vector\n\nAn attacker who can supply crafted serialized Channel bytes to the client application \u2014 for example, by compromising a local channel file, injecting data through an application that accepts Channel bytes from external sources, or exploiting a separate write primitive \u2014 can achieve RCE via gadget chain exploitation when deSerializeChannel() processes those bytes. The risk is highest in deployments that accept Channel data from sources outside the client\u0027s direct control. Note: channel data is not transmitted from Fabric peers; this is a client-side deserialization surface.\n\n## Proof of Concept\n\n```java\n// Generate malicious payload with ysoserial:\n// java -jar ysoserial.jar CommonsCollections6 \"touch /tmp/pwned\" \u003e malicious_channel.ser\n\n// Victim code:\nbyte[] maliciousBytes = Files.readAllBytes(Paths.get(\"malicious_channel.ser\"));\nChannel channel = client.deSerializeChannel(maliciousBytes); // RCE fires here\n```\n\n## Notes on Deprecation\n\nfabric-sdk-java is deprecated as of Hyperledger Fabric v2.5 (replaced by `org.hyperledger.fabric:fabric-gateway`). However, organizations that have not yet migrated remain fully exposed. Automated dependency scanners (Snyk, Dependabot) cannot alert users without a published GHSA. This advisory is filed to ensure those users are notified and directed to migrate.\n\n## Fix\n\nFor the deprecated SDK: add `ObjectInputFilter` to whitelist only expected classes:\n\n```java\nObjectInputFilter filter = ObjectInputFilter.Config.createFilter(\n \"org.hyperledger.fabric.sdk.*;java.util.*;java.lang.*;!*\"\n);\nois.setObjectInputFilter(filter);\n```\n\n**The recommended remediation is migration to `org.hyperledger.fabric:fabric-gateway`**, which does not use Java serialization.\n\n## Resources\n\n- CWE-502: Deserialization of Untrusted Data\n- Migration guide: https://hyperledger.github.io/fabric-gateway/\n\n## Credits\n\nFound by [Martin Brodeur (brodmart)](https://github.com/brodmart) via independent security research.",
"id": "GHSA-prf8-cf2x-rhx7",
"modified": "2026-05-20T22:56:25Z",
"published": "2026-04-29T20:41:58Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/hyperledger/fabric/security/advisories/GHSA-prf8-cf2x-rhx7"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41586"
},
{
"type": "PACKAGE",
"url": "https://github.com/hyperledger/fabric-sdk-java"
},
{
"type": "WEB",
"url": "https://hyperledger.github.io/fabric-gateway"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "fabric-sdk-java has ObjectInputStream.readObject() without ObjectInputFilter, which allows Java deserialization RCE"
}
GHSA-PRP9-9GXW-38J8
Vulnerability from github – Published: 2022-05-24 19:05 – Updated: 2022-05-24 19:05A deserialization flaw was found in Apache Chainsaw versions prior to 2.1.0 which could lead to malicious code execution.
{
"affected": [],
"aliases": [
"CVE-2020-9493"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-06-16T08:15:00Z",
"severity": "CRITICAL"
},
"details": "A deserialization flaw was found in Apache Chainsaw versions prior to 2.1.0 which could lead to malicious code execution.",
"id": "GHSA-prp9-9gxw-38j8",
"modified": "2022-05-24T19:05:32Z",
"published": "2022-05-24T19:05:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-9493"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/r50d389c613ba6062a26aa57e163c09bfee4ff2d95d67331d75265b83@%3Cannounce.apache.org%3E"
},
{
"type": "WEB",
"url": "https://www.openwall.com/lists/oss-security/2021/06/16/1"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2021/06/16/1"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2022/01/18/5"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PV2V-6W2V-97X6
Vulnerability from github – Published: 2026-05-21 21:30 – Updated: 2026-06-23 22:57Concrete CMS 9.5.0 and below is vulnerable to Remote Code Execution due to insecure deserialization occurring in the ExpressEntryList block controller. An rogue administrator with privileges to add blocks to an area can bypass the intended protection mechanism (_fromCIF === true), which normally restricts malicious inputs over form POST requests, by leveraging the REST API functionality. Because the REST API parses requests using json_decode(), the string "true" is evaluated as a strict PHP Boolean(true). This bypass allows the attacker to inject a malicious serialized payload into the block's filterFields database column. The payload will subsequently be executed when the block's data is viewed or edited by an administrator leading to complete server takeover (RCE). Concrete CMS thanks Nguyễn Văn Thiện https://github.com/Thien225409 for reporting this issue.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "concrete5/concrete5"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "9.5.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-8135"
],
"database_specific": {
"cwe_ids": [
"CWE-502"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-23T22:57:59Z",
"nvd_published_at": "2026-05-21T21:16:32Z",
"severity": "HIGH"
},
"details": "Concrete CMS 9.5.0 and below is vulnerable to Remote Code Execution due to insecure deserialization occurring in the\u00a0ExpressEntryList\u00a0block controller. An rogue administrator with privileges to add blocks to an area can bypass the intended protection mechanism (_fromCIF === true), which normally restricts malicious inputs over form POST requests, by leveraging the REST API functionality. Because the REST API parses requests using json_decode(), the string \"true\" is evaluated as a strict PHP Boolean(true).\u00a0 This bypass allows the attacker to inject a malicious serialized payload \u00a0into the block\u0027s filterFields database column. The payload will subsequently be executed when the block\u0027s data is viewed or edited by an administrator leading to complete server takeover (RCE). Concrete CMS thanks Nguy\u1ec5n V\u0103n Thi\u1ec7n https://github.com/Thien225409 \u00a0for reporting this issue.",
"id": "GHSA-pv2v-6w2v-97x6",
"modified": "2026-06-23T22:57:59Z",
"published": "2026-05-21T21:30:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8135"
},
{
"type": "WEB",
"url": "https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes"
},
{
"type": "PACKAGE",
"url": "https://github.com/concretecms/concretecms"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
"type": "CVSS_V4"
}
],
"summary": "Concrete CMS Vulnerable to Deserialization of Untrusted Data"
}
Mitigation
If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
Mitigation
When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
Mitigation
Explicitly define a final object() to prevent deserialization.
Mitigation
- Make fields transient to protect them from deserialization.
- An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.
Mitigation
Avoid having unnecessary types or gadgets (a sequence of instances and method invocations that can self-execute during the deserialization process, often found in libraries) available that can be leveraged for malicious ends. This limits the potential for unintended or unauthorized types and gadgets to be leveraged by the attacker. Add only acceptable classes to an allowlist. Note: new gadgets are constantly being discovered, so this alone is not a sufficient mitigation.
Mitigation
Employ cryptography of the data or code for protection. However, it's important to note that it would still be client-side security. This is risky because if the client is compromised then the security implemented on the client (the cryptography) can be bypassed.
Mitigation MIT-29
Strategy: Firewall
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].
CAPEC-586: Object Injection
An adversary attempts to exploit an application by injecting additional, malicious content during its processing of serialized objects. Developers leverage serialization in order to convert data or state into a static, binary format for saving to disk or transferring over a network. These objects are then deserialized when needed to recover the data/state. By injecting a malformed object into a vulnerable application, an adversary can potentially compromise the application by manipulating the deserialization process. This can result in a number of unwanted outcomes, including remote code execution.