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Overview
Version 1.6.1 of the Flash Payments package graphql-upload-minimal is vulnerable to prototype pollution. This vulnerability, located in the processRequest() function, allows an attacker to inject special property names into the operations.variables object and pollute global object prototypes, ultimately impacting the entire Node.js process.
Description
graphql-upload-minimal is a lightweight Node.js middleware package that implements the GraphQL multipart request specification, enabling file uploads in GraphQL servers. It parses multipart/form-data requests and maps uploaded files into the GraphQL operations object, making them accessible to resolvers.
The vulnerability exists in the processRequest() function, which handles multipart file upload requests. It processes a user-supplied map parameter that determines where uploaded files should be placed within the GraphQL operations.variables object.
The issue occurs because user-supplied property paths are not validated before being resolved and written into the target object. Special JavaScript property names such as __proto__, __constructor__, and prototype are not restricted, allowing crafted paths to traverse the prototype chain and modify Object.prototype.
Because Object.prototype is the base prototype from which most JavaScript objects inherit, altering it results in global prototype pollution across the Node.js process. Once polluted, manipulated properties may be inherited by all subsequently created objects for the lifetime of the process.
Impact
Because Object.prototype is the foundational prototype for most JavaScript objects, modifying it can affect the behavior of all Node.js processes. Since the impact extends across the entire Node.js process and persists until the service is restarted, it can potentially result in logic corruption, denial of service, or unintended privilege escalation.
Solution
Users should upgrade to graphql-upload-minimal version 1.6.3 or later, which can be found at https://github.com/flash-oss/graphql-upload-minimal/tree/master . The patched release introduces safeguards to prevent unsafe prototype-chain property assignments during multipart file upload processing.
Acknowledgements
Thanks to Maor Caplan from Alma Security for reporting this vulnerability. This document was written by Michael Bragg.

Overview
Two unsafe pickle deserialization vulnerabilities have been discovered in the SGLang open-source project, one within the tool’s multimodal generation module and another within the Encoder Parallel Disaggregation system. SGLang is a serving framework for large language models (LLMs) and multimodal models. These vulnerabilities, tracked as CVE-2026-3059 and CVE-2026-3060, allow an attacker to provide a malicious pickle file to a device using SGLang’s multimodal generation system or the encoder parallel disaggregation system, enabling code execution. CVE-2026-3989 allows an attacker to provide a malicious pickle file that, when attempted to be replayed with the replay_request_dump.py script, will result in code execution. It is recommended that project maintainers avoid implementing Pickle functions due to the inherent security risks.
Description
SGLang is a framework for serving various large language models (LLMs) and multimodal AI models, supporting models such as Qwen, DeepSeek, Mistral, and Skywork, and is compatible with OpenAI APIs. Two unsafe pickle deserialization vulnerabilities have been identified in the project, tracked as CVE-2026-3059 and CVE-2026-3060.
CVE-2026-3059
SGLangs multimodal generation module is vulnerable to unauthenticated remote code execution through the ZMQ broker, which deserializes untrusted data using pickle.loads() without authentication.
CVE-2026-3060
SGLangs encoder parallel disaggregation system is vulnerable to unauthenticated remote code execution through the disaggregation module, which deserializes untrusted data using pickle.loads() without authentication.
SGLang is vulnerable to CVE-2026-3059 when the multimodal generation system is enabled, and to CVE-2026-3060 when the encoder parallel disaggregation system is enabled. If either condition is met and an attacker knows the TCP port on which the ZMQ broker is listening and can send requests to the server, they can exploit the vulnerability by sending a malicious pickle file to the broker, which will then deserialize it.
CVE-2026-3989
SGLangs replay_request_dump.py contains an insecure pickle.load() without validation and proper deserialization. An attacker can take advantage of this by providing a malicious .pkl file, which will execute the attackers code on the device running the script.
The SGLang project’s replay_request_dump.py script uses pickle.load() without trust validation, allowing for arbitrary code execution if an attacker can control the pickle file contents. This vulnerability has low applicability but high impact, and can be exploited if an attacker can provide a malicious pickle file or write to the crash dump directory, potentially through social engineering or by compromising a directory where crash dump information is automatically saved. The script, intended to replay crash dump information, poses a risk if an attacker can manipulate the input files or directories used by the script.
The use of Pickle is strongly discouraged due to its inherent security risks. Deserializing a pickle file with pickle.loads() can lead to Remote Code Execution (RCE) if an attacker can provide a malicious file. This is because the pickle file format stores not only data but also instructions on how to reconstruct the object, which are executed during deserialization. As a result, an attacker can potentially execute arbitrary Python code.
To mitigate these risks, projects should consider implementing safer serialization formats, such as JSON or XML, or using tools like msgpack to perform more data-driven serialization and deserialization instead of open-ended capabilities such as pickle. This can help prevent RCE attacks and ensure the secure exchange of data.
Impact
An attacker who can send crafted messages to the ZeroMQ interface may trigger unsafe pickle deserialization in SGLang when certain features are enabled, potentially leading to remote code execution. Additionally, an attacker who can provide a malicious pickle file in the context of a crash dump may also exploit CVE-2026-3989. Successful exploitation could allow arbitrary code execution in the context of the SGLang service, potentially leading to host compromise, lateral movement, data exfiltration, or denial-of-service (DoS) attacks. Deployments that expose the affected interface to untrusted networks are at the highest risk of exploitation.
Solution
Users of SGLang should restrict access to the service interfaces and ensure they are not exposed to untrusted networks. Proper network segmentation and access controls should be implemented to prevent unauthorized interaction with the ZeroMQ endpoints. During coordinated disclosure, no vendor statement was obtained. A proposed patch was submitted to the maintainers, but no response was received at the time of publication.
Acknowledgements
Thanks to the reporter, Igor Stepansky. Thank you to Gregory Bowers for additional research assistance during coordination.This document was written by Christopher Cullen.

Overview
Malformed ZIP headers can cause antivirus and endpoint detection and response software (EDR) to produce false negatives. Despite the presence of malformed headers, some extraction software is still able to decompress the ZIP archive, allowing potentially malicious payloads to run upon file decompression.
Description
ZIP archives contain metadata such as compression method, flags, and version information. Antivirus engines typically rely on this metadata to determine how to preprocess files before scanning. If an attacker modifies the compression method field, antivirus software may fail to properly decompress the file, and will therefore be unable to analyze the actual payload.
After antivirus evasion, the payload can be recovered by using a custom loader that ignores the declared Method field and instead decompresses embedded data directly. This allows the attacker to hide malicious content from antivirus engines while still being able to recover it programmatically.
Notably, standard extraction tools (e.g.: 7‑Zip, unzip, bsdtar, Python’s zipfile) trust the declared compression method and attempt decompression, but then fail with CRC or “unsupported method” errors. These tools do not extract the payload and do not expose the underlying data.
This vulnerability is similar to VU#968818, CVE-2004-0935.
Impact
A remote attacker may craft a ZIP archive with tampered metadata that prevents antivirus or EDR software from properly decompressing and inspecting its contents. The file can thereby evade full analysis, though many products will still flag it as corrupted.
To execute malicious code, however, a user must extract or further process the archive. Standard extraction tools may or may not reveal the hidden payload. It is possible that a custom loader that ignores the declared compression method could recover and execute the concealed content.
Solution
Antivirus and EDR vendors should not rely solely on declared archive metadata to determine content handling. Scanners should have more aggressive detection modes to validate compression method fields against actual content characteristics, and flag inconsistencies for further inspection.
Users are encouraged to contact their antivirus or EDR providers to identify whether they are vulnerable and obtain guidance on additional mitigation options.
Acknowledgements
Thanks to the reporter, Christopher Aziz. This document was written by Laurie Tyzenhaus.

Overview
The Rakuten Viber messaging app for Android V25.7.2.0g and Windows V25.6.0.0-V25.8.1.0, has a flaw in its TLS handshake implementation when using the Cloak proxy configuration. This flaw allows for easy identification of proxy usage, potentially compromising user anonymity.
Description
Rakuten Viber can be configured to use a proxy server. Multiple proxy configurations, including Cloak, are supported. Rakuten Viber in Android V25.7.2.0g and Windows V25.6.0.0–V25.8.1.0 exhibits a flaw in the TLS handshake implementation for Cloak mode. Cloak mode is designed to hide the fact that a proxy or VPN is in use.
However, the Cloak proxy mode has a rigid and easily identified fingerprint, making it trivially identifiable by Deep Packet Inspection (DPI) systems. This allows networks to block Viber traffic, undermining the app’s ability to circumvent censorship and potentially leading to denial of service in certain cases.
Impact
The Cloak-mode proxy traffic fails to hide the use of a proxy. The outgoing data is easily identifiable due to the rigid fingerprint and no longer appears to be normal browser TLS behavior. The user has no indication the proxy is not protecting their data.
Solution
Windows users should upgrade to V27.3.0.0 or later, and Android users should upgrade to V27.2.0.0g or later.
For continued support, Windows users can implement automatic updates for Viber.
Acknowledgements
Thanks to the reporter Oleksii Gaienko, an independent security researcher. This document was written by Laurie Tyzenhaus.

Overview
A command injection vulnerability was identified in the MS-Agent framework that can be triggered through unsanitized prompt-derived input. An attacker can craft untrusted input introduced via a chat prompt or other external content sources, resulting in arbitrary command execution on the target system(s) where the MS-Agent framework is deployed. No patch or vendor statement was obtained during the coordination process.
Description
MS-Agent is a lightweight framework that enables agents to perform autonomous task execution and tool invocation. The MS-Agent framework includes several features, including a Shell tool that enables execution of commands on the target operating system to complete agentic actions.
A vulnerability has been identified that allows unsanitized input to be executed through the Shell tool. This occurs because the software does not sufficiently verify and sanitize content before execution. As a result, an attacker can leverage prompt injection techniques to influence the agent into executing unintended shell commands when interacting with attacker-controlled content.
The Shell tool relies on regular expression–based filtering in the check_safe() method, which is intended to restrict unsafe commands. The implemented default denylist can be bypassed, allowing crafted input to evade validation checks and reach the shell execution layer.
The vulnerability is tracked as:
CVE-2026-2256
Command injection vulnerability in ModelScope’s ms-agent allows an attacker to execute arbitrary operating system commands through crafted prompt-derived input.
This vulnerability may be exploited when the agent is instructed to process or retrieve external content, such as analyzing code, summarizing documents, or performing other tasks that involve interacting with attacker-controlled data. If the retrieved or processed content contains malicious command sequences that bypass the check_safe() validation, the agent may forward those commands to the Shell tool for execution.
The use of a regular expression denylist in the check_safe() method is insufficient to prevent command injection. Denylist-based filtering is inherently fragile and can often be bypassed through encoding, command obfuscation, or alternative shell syntax. In this case, the filtering logic can be circumvented, enabling arbitrary command execution within the execution context of the agent process.
Impact
An attacker who successfully exploits this vulnerability may execute arbitrary operating system commands on the target with the privileges of the MS-Agent process. This may allow modification of system files, lateral movement within the environment, establishment of persistence mechanisms, or exfiltration of sensitive data accessible to the agent.
Solution
No statement was provided by the vendor during coordination efforts. Users should deploy MS-Agent only in environments where ingested content is trusted, validated, or sanitized. Agents with shell execution capabilities should be sandboxed or executed with least-privilege permissions. Additional mitigation strategies include replacing denylist-based filtering with strict allowlists and implementing stronger isolation boundaries for tool execution.
Acknowledgements
Thanks to the reporter, Itamar Yochpaz, for this report. Document written by Christopher Cullen.

Overview
A path traversal vulnerability leading to arbitrary file write exist in PyMuPDF version 1.26.5, within the ‘embedded_get’ function in ‘main.py’. This vulnerability is caused by improper handling of untrusted embedded file metadata, which is used directly as an output path, enabling attackers to write files to arbitrary locations on the local system.
Description
PyMuPDF is a Python interface to the MuPDF document rendering engine, providing capabilities for parsing, rendering, searching, and modifying PDF documents.
The ‘embedded_get’ function in PyMuPDF is responsible for opening the provided PDF along with fetching metadata, such as the file name, if using ‘args.output’ it specifies were the file will be written to on the local system. When ‘args.output’ is not provided, the ‘embedded_get’ function falls back to embedded-file metadata, and opens that value in write-binary mode. Since write-binary mode has no constrictions or safety checks it can write anywhere to the local system.
If the derived output path is not supplied by using ‘args.output’, a crafted PDF can be used to target a location on the local system by using the PDF’s name. When an extracted embedded file using ‘embedded_get’ without specified ‘args.output, the tool can write the extracted content outside the intended directory, potentially to paths on the local system.
Impact
Successful exploitation can result in arbitrary file writing to locations permitted by the executing user. If done under an account with elevated privileges, it may overwrite system files. This can lead to privilege escalation, service disruption, or security bypass. ### Overview
A path traversal vulnerability leading to arbitrary file write exists in PyMuPDF version 1.26.5, within the embedded_get function in __main__.py. This vulnerability is caused by improper handling of untrusted embedded file metadata, which is used directly as an output path, enabling attackers to write files to arbitrary locations on the local system.
Description
PyMuPDF is a Python interface to the MuPDF document rendering engine, providing capabilities for parsing, rendering, searching, and modifying PDF documents.
The embedded_get function in PyMuPDF is responsible for opening the provided PDF along with fetching metadata, such as the file name. If using args.output, it specifies where the file will be written on the local system. When args.output is not provided, the embedded_get function falls back to embedded file metadata and opens that value in write-binary mode. Since write-binary mode has no constrictions nor safety checks, it can write to anywhere on the local system.
If the derived output path is not supplied with args.output, a crafted PDF can be used to target a location on the local system using the name of the PDF. When an embedded file is extracted using embedded_get without specified args.output, the tool can write the extracted content outside the intended directory, potentially to paths on the local system.
Impact
Successful exploitation can result in arbitrary file writing to locations permitted by the executing user. If done under an account with elevated privileges, it may overwrite system files. This can lead to privilege escalation, service disruption, or security bypass.
Solution
PyMuPDF has released version 1.26.7 to address this vulnerability. Affected users are encouraged to update as soon as possible.
Acknowledgements
Thanks to the reporter UKO. This document was written by Michael Bragg.
Solution
PyMuPDF has released version 1.26.7 to address this vulnerability. Affected users are encouraged to update as soon as possible.
Acknowledgements
Thanks to the reporter Jangwoo Choe (UKO). This document was written by Michael Bragg.

Overview
A prototype pollution vulnerability present in CASL Ability versions 2.4.0 through 6.7.4 is triggered through the rulesToFields() function in the extra module. The program’s library contains a method called setByPath() that does not properly sanitize property names, allowing attackers to add or modify properties on an object’s prototype.
Description
The CASL library provides a robust suite for managing attribute-based access control across various components, services, and queries. Access control is defined with a set of rule conditions. The library provides a set of default values for these conditions.
In JavaScript libraries like CASL, prototypes are template objects that serve as blueprints and inform the properties of their child objects. By exploiting this prototype pollution vulnerability, an attacker can inject arbitrary properties into global object prototypes, thereby affecting all child objects that inherit from them. The issue arises from a flaw in the setByPath() function, a component of the rulesToFields() function in the extra module.
The setByPath() function is intended to safely update only permitted fields; however, it fails to properly sanitize path segments before using them as object property keys. Consequently, special property names such as prototype and constructor are accepted as valid keys, allowing an attacker to modify the properties of object prototypes and constructor classes. Furthermore, the _proto_ special property can be used to traverse the prototype chain and ultimately write to Object.prototype, the root prototype of all objects. By polluting Object.prototype, an attacker can add arbitrary properties to all objects and compromise the prototype chain throughout the Node.js process.
Impact
As Object.prototype is the root prototype that all JavaScript objects inherit from, changes to its properties can be significant, allowing an attacker to execute arbitrary code and potentially leading to a complete system compromise. Additionally, an attacker can bypass intended authorization logic, allowing unauthorized access to sensitive resources. Furthermore, changes to Object.prototype can cause unintended behavior in application code, leading to logic manipulation and potentially allowing an attacker to perform actions that would normally be restricted.
Manipulating properties in Object.prototype can also cause crashes or unexpected behavior if polluted properties do not match expected types in the application code, leading to a denial of service. Overall, the Object.prototype pollution vulnerability poses a significant risk to applications and systems. Because the vulnerability exists in the CASL library, which is used by multiple applications and services, a single exploit can have a ripple effect, compromising multiple systems and potentially leading to a widespread security breach.
Solution
Users of the library should upgrade to version 6.7.5 or later, found at https://github.com/stalniy/casl/tree/master/packages/casl-ability.
Acknowledgements
Thanks to Maor Caplan from the Alma Security for coordinating the disclosure of this vulnerability. This document was written by Ayushi Kriplani and Dr. E. Drennan, CISSP.