OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions 3.4.0 through 3.4.12, a crafted HTJ2K-compressed EXR file causes an unconditional process abort in any application that calls exr_start_read() on untrusted input, resulting in denial of service. The crash is triggered by a QCD marker whose lower five bits are zero, which OpenEXR passes into the vendored OpenJPH library while constructing the codestream and evaluating its quantization delta parameters. OpenJPH uses an assertion rather than a recoverable error to validate those bits, so any invalid value calls abort() directly and cannot be intercepted by surrounding error handling, a problem compounded by OpenEXR wrapping only its internal HT header parser in error handling while leaving the later codestream read and construction calls unprotected. This issue has been resolved in version 3.4.13.
Weakness
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
Extended Description
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.