Heap-buffer-overflow write in FFmpeg EXR dwa_uncompress
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 8.0
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
When decoding an OpenEXR file that uses DWAA or DWAB compression, there's an implicit assumption that all image channels have the same pixel type (and size), and that if there are four channels, the first four are "B", "G", "R" and "A". The channel parsing code can be found in decode_header. The buffer td->uncompressed_data is allocated in decode_block based on the xsize, ysize and computed current_channel_offset. The function dwa_uncompress then assumes at [5] that if there are 4 channels, these are "B", "G", "R" and "A", and in the calculations at [6] and [7] that all channels are of the same type, which matches the type of the main color channels. If we set the main color channels to a 4-byte type and add duplicate or unknown channels of the 2-byte EXR_HALF type, then the addition at [7] will increment the pointer by 4-bytes * xsize * nb_channels, which will exceed the allocated buffer. We recommend upgrading to version 8.0 or beyond.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- EXR
From 7.1.1 · fixed in 8.0