CVE-2026-48510

CVE-2026-48510 affects MessagePack-CSharp (C#) prior to 2.5.301 and 3.1.7. When decompressing Lz4Block or Lz4BlockArray payloads, the library reads declared uncompressed lengths from the wire and allocates output buffers before validating the data, allowing a small payload to trigger a large allo...

CVE-2026-48510 MessagePack-CSharp: LZ4 decompression allocates from unbounded declared output lengths

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, when MessagePack-CSharp decompresses Lz4Block or Lz4BlockArray payloads, it reads declared uncompressed lengths from the wire and allocates output buffers based on those lengths before validating that the compressed...

CVE-2026-48510 MessagePack-CSharp: LZ4 decompression allocates from unbounded declared output lengths

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, when MessagePack-CSharp decompresses Lz4Block or Lz4BlockArray payloads, it reads declared uncompressed lengths from the wire and allocates output buffers based on those lengths before validating that the compressed...

urllib3: urllib3: Unbounded decompression chain leads to resource exhaustion

A flaw was found in urllib3 Python library that could lead to a Denial of Service condition. A remote, malicious server can exploit this flaw by responding to a client request with an HTTP message that uses an excessive number of chained compression algorithms. This unlimited decompression chain...

urllib3: urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API)

urllib3 is an HTTP client library for Python. urllib3's streaming API is designed for the efficient handling of large HTTP responses by reading the content in chunks, rather than loading the entire response body into memory at once. urllib3 can perform decoding or decompression based on the HTTP...

urllib3: urllib3 Streaming API improperly handles highly compressed data

A decompression handling flaw has been discovered in urllib3. When streaming a compressed response, urllib3 can perform decoding or decompression based on the HTTP Content-Encoding header e.g., gzip, deflate, br, or zstd. The library must read compressed data from the network and decompress it...

PYSEC-2026-2111

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a compressed payload in specific situations that could be...

EUVD-2026-38315

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a compressed payload in specific situations that could be...

urllib3: urllib3: Denial of Service due to excessive HTTP response decompression

A flaw was found in urllib3, an HTTP client library for Python. This vulnerability allows a remote attacker to cause excessive resource consumption, such as high CPU usage and massive memory allocation, on the client side. This occurs when urllib3 attempts to decompress an entire HTTP response,...

urllib3: urllib3: Denial of Service due to excessive HTTP response decompression

A flaw was found in urllib3, an HTTP client library for Python. This vulnerability allows a remote attacker to cause excessive resource consumption, such as high CPU usage and massive memory allocation, on the client side. This occurs when urllib3 attempts to decompress an entire HTTP response,...

ALSA-2026:28000 Important: python-urllib3 security update

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems. Security Fixes:...

Linux Distros Unpatched Vulnerability : CVE-2026-54278

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to ...

RHEL 8 : Red Hat OpenStack Platform 17.1 (python-urllib3) (RHSA-2026:28043)

The remote Redhat Enterprise Linux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2026:28043 advisory. Python HTTP module with connection pooling and file POST abilities. Security Fixes: urllib3: Unbounded decompression chain leads to resourc...

Linux Distros Unpatched Vulnerability : CVE-2026-9375

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - urllib3 version 2.6.3 is vulnerable to a decompression bomb bypass in its streaming API preloadcontent=False when using Brotli support. The issue arises due to...

py7zr: Decompression bomb (zip bomb) denial of service via unchecked extraction size

py7zr's Worker.decompress extracts archive entries without tracking total decompressed size. A crafted .7z file can exhaust disk or memory before the extraction completes. Measured: 15.6 KB archive → 100 MB output 6,556:1 ratio. Proof of concept: python import py7zr, tempfile, os create bomb:...

GHSA-GJRG-MPP7-G774 py7zr: Decompression bomb (zip bomb) denial of service via unchecked extraction size

py7zr's Worker.decompress extracts archive entries without tracking total decompressed size. A crafted .7z file can exhaust disk or memory before the extraction completes. Measured: 15.6 KB archive → 100 MB output 6,556:1 ratio. Proof of concept: python import py7zr, tempfile, os create bomb:...

Ultimate Sitemap Parser (USP): Gzip Decompression Bomb Bypasses Sitemap Size Limit

Gzip Decompression Bomb Bypasses Sitemap Size Limit Summary ultimate-sitemap-parser enforces a 100 MiB size limit on sitemap responses, but applies it only to the compressed bytes received over the network. When a .gz sitemap is fetched, usp/helpers.py:239 calls gziplib.decompressdata with no...

GHSA-8823-QG2X-PV9F Ultimate Sitemap Parser (USP): Gzip Decompression Bomb Bypasses Sitemap Size Limit

Gzip Decompression Bomb Bypasses Sitemap Size Limit Summary ultimate-sitemap-parser enforces a 100 MiB size limit on sitemap responses, but applies it only to the compressed bytes received over the network. When a .gz sitemap is fetched, usp/helpers.py:239 calls gziplib.decompressdata with no...

CVE-2026-9375

urllib3 version 2.6.3 is vulnerable to a decompression bomb bypass in its streaming API preloadcontent=False when using Brotli support. The issue arises due to three independent code paths in response.py that bypass the maxlength protection introduced in version 2.6.0 to mitigate CVE-2025-66471...

DEBIAN-CVE-2026-9375

urllib3 version 2.6.3 is vulnerable to a decompression bomb bypass in its streaming API preloadcontent=False when using Brotli support. The issue arises due to three independent code paths in response.py that bypass the maxlength protection introduced in version 2.6.0 to mitigate CVE-2025-66471...