CVE-2026-54135: AirSane has a Remote Denial of Service (OOM) via Unvalidated Content-Length in HTTP Server

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-11 · updated 2026-09-30
Weakness: CWE-400

Description

AirSane is a SANE frontend, and a scanner server that supports Apple's AirScan protocol. Versions prior to 0.4.12 have a vulnerability in the custom HTTP server implementation of AirSane that allows a remote unauthenticated attacker to cause a Denial of Service (DoS) via memory exhaustion (OOM). In httpserver.cpp, the HttpServer::Request::content function reads the Content-Length header and directly passes this value to std::string::resize() without any upper-bound validation or safe parsing. An attacker can send an HTTP POST request with an artificially large Content-Length value. This forces the daemon to attempt allocating gigabytes of memory, resulting in a std::bad_alloc exception and immediately crashing the AirSane process. Additionally, providing non-numeric characters in the Content-Length header leads to undefined behavior (NaN to integer conversion) due to the lack of error handling during header parsing. Version 0.4.12 patches the issue.

Affected products

SimulPiscator AirSane: before 0.4.12

References

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