PYSEC-2026-1202 Authlib : JWE zip=DEF decompression bomb enables DoS

Summary Authlib’s JWE zip=DEF path performs unbounded DEFLATE decompression. A very small ciphertext can expand into tens or hundreds of megabytes on decrypt, allowing an attacker who can supply decryptable tokens to exhaust memory and CPU and cause denial of service. Details - Affected component...

Litestar X-Forwarded-For Header Spoofing Vulnerability Enables Rate Limit Evasion

While testing Litestar's RateLimitMiddleware, I discovered that rate limits can be completely bypassed by manipulating the X-Forwarded-For header. This renders IP-based rate limiting ineffective against determined attackers. The ProblemLitestar's RateLimitMiddleware uses cachekeyfromrequest to...

PYSEC-2026-1553 Litestar X-Forwarded-For Header Spoofing Vulnerability Enables Rate Limit Evasion

While testing Litestar's RateLimitMiddleware, I discovered that rate limits can be completely bypassed by manipulating the X-Forwarded-For header. This renders IP-based rate limiting ineffective against determined attackers. The Problem Litestar's RateLimitMiddleware uses cachekeyfromrequest to...

PYSEC-2026-1200 Authlib: JWS/JWT accepts unknown crit headers (RFC violation → possible authz bypass)

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...

ESP-IDF web_server basic auth bypass using empty or incomplete Authorization header

SummaryOn the ESP-IDF platform, ESPHome's webserver authentication check can pass incorrectly when the client-supplied base64-encoded Authorization value is empty or is a substring of the correct value e.g., correct username with partial password. This allows access to webserver functionality...

vllm API endpoints vulnerable to Denial of Service Attacks

SummaryA Denial of Service DoS vulnerability can be triggered by sending a single HTTP GET request with an extremely large header to an HTTP endpoint. This results in server memory exhaustion, potentially leading to a crash or unresponsiveness. The attack does not require authentication, making i...

h2 allows HTTP Request Smuggling due to illegal characters in headers

SummaryHTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request...

PYSEC-2026-2021 vllm API endpoints vulnerable to Denial of Service Attacks

Summary A Denial of Service DoS vulnerability can be triggered by sending a single HTTP GET request with an extremely large header to an HTTP endpoint. This results in server memory exhaustion, potentially leading to a crash or unresponsiveness. The attack does not require authentication, making ...

PYSEC-2026-1435 h2 allows HTTP Request Smuggling due to illegal characters in headers

Summary HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request...

OpenEXR Out-Of-Memory via Unbounded File Header Values

SummaryThe OpenEXR file format defines many information about the final image inside of the file header, such as the size of data/display window.The application trusts the value of dataWindow size provided in the header of the input file, and performs computations based on this value.This may...

OpenEXR Heap-Based Buffer Overflow in Deep Scanline Parsing via Forged Unpacked Size

SummaryThe OpenEXRCore code is vulnerable to a heap-based buffer overflow during a write operation when decompressing ZIPS-packed deep scan-line EXR files with a maliciously forged chunk header. DetailsWhen parsing STORAGEDEEPSCANLINE chunks from an EXR file, the following code from...

PYSEC-2026-1747 OpenEXR Heap-Based Buffer Overflow in Deep Scanline Parsing via Forged Unpacked Size

Summary The OpenEXRCore code is vulnerable to a heap-based buffer overflow during a write operation when decompressing ZIPS-packed deep scan-line EXR files with a maliciously forged chunk header. Details When parsing STORAGEDEEPSCANLINE chunks from an EXR file, the following code from...

PYSEC-2026-1749 OpenEXR Out-Of-Memory via Unbounded File Header Values

Summary The OpenEXR file format defines many information about the final image inside of the file header, such as the size of data/display window. The application trusts the value of dataWindow size provided in the header of the input file, and performs computations based on this value. This may...

pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages

SummaryAny unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. DetailsAny unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. This ...

PYSEC-2026-1822 pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages

Summary Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. Details Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. Thi...

Flask-AppBuilder open redirect vulnerability using HTTP host injection

ImpactFlask-AppBuilder prior to 4.6.2 would allow for a malicious unauthenticated actor to perform an open redirect by manipulating the Host header in HTTP requests. PatchesFlask-AppBuilder 4.6.2 introduced the FABSAFEREDIRECTHOSTS configuration variable, which allows administrators to explicitly...

PYSEC-2026-1379 Flask-AppBuilder open redirect vulnerability using HTTP host injection

Impact Flask-AppBuilder prior to 4.6.2 would allow for a malicious unauthenticated actor to perform an open redirect by manipulating the Host header in HTTP requests. Patches Flask-AppBuilder 4.6.2 introduced the FABSAFEREDIRECTHOSTS configuration variable, which allows administrators to explicit...

Django: DomainNameValidator permits newline characters that may enable HTTP header injection

An issue was discovered in Django 6.0 before 6.0.7 and 5.2 before 5.2.16. DomainNameValidator does not prohibit newlines in domain names unless used via a form field, since CharField strips newlines. If an application uses values with newlines in an HTTP response, header injection can occur. Djan...

GHSA-8QCX-XF44-272X Django: DomainNameValidator permits newline characters that may enable HTTP header injection

An issue was discovered in Django 6.0 before 6.0.7 and 5.2 before 5.2.16. DomainNameValidator does not prohibit newlines in domain names unless used via a form field, since CharField strips newlines. If an application uses values with newlines in an HTTP response, header injection can occur. Djan...

GO-2026-5829 Nezha Monitoring: OAuth2 Redirect URL — Host Header Injection in github.com/nezhahq/nezha

Nezha Monitoring: OAuth2 Redirect URL — Host Header Injection in github.com/nezhahq/nezha. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. If this is causing false-positive reports from vulnerability...