CVE-2018-18584: A CAB file with a Quantum-compressed block of exactly 38912 bytes will write one byte beyond the end of the input buffer

In mspack/cab.h in libmspack before 0.8alpha and cabextract before 1.8, the CAB
block input buffer is one byte too small for the maximal Quantum block, leading to an out-of-bounds write.

References:

https://www.cabextract.org.uk/libmspack/
https://nvd.nist.gov/vuln/detail/CVE-2018-18584

Patch:

https://github.com/kyz/libmspack/commit/40ef1b4093d77ad3a5cfcee1f5cb6108b3a3bcc2

CVE-2018-18585: CHM files with blank filenames (by having embedded nulls) are allowed, which trips up clients that expect non-blank filenames

chmd_read_headers in mspack/chmd.c in libmspack before 0.8alpha accepts a filename
that has ‘\0’ as its first or second character (such as the “/\0” name).

References:

https://www.cabextract.org.uk/libmspack/
https://nvd.nist.gov/vuln/detail/CVE-2018-18585

Patch:

https://github.com/kyz/libmspack/commit/8759da8db6ec9e866cb8eb143313f397f925bb4f

CVE-2018-18586: chmextract makes no attempt to protect you from relative/absolute paths in CHM filenames

DISPUTED chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application.

References:

https://www.cabextract.org.uk/libmspack/
https://nvd.nist.gov/vuln/detail/CVE-2018-18586

Patch:

https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d

(from redmine: issue id 9663, created on 2018-11-21, closed on 2018-11-28)

• Relations:
  • parent #9662 (closed)
• Changesets:
  • Revision 3a49d88a by Natanael Copa on 2018-11-27T12:30:37Z:

main/libmspack: security upgrade to 0.8_alpha

CVE-2018-18584, CVE-2018-18585, CVE-2018-18586

fixes #9663