Qualifier Challenge - NRFIN_00008

Original Versions

Known Vulnerabilities

  • CWE-680 - Integer Overflow to Buffer Overflow
  • CWEs are listed as indicated by the challenge author.


  • ForAllSecure: 0.93
  • CSDS: 0.75
  • DeepRed: 0.59
  • TrailofBits: 0.14
  • CodeJitsu: 0.0
  • Disekt: 0.0
  • TECHx: 0.0
  • Shellphish: 0.0
  • FuzzBOMB: 0.0
  • The maximum score for each challenge in CQE is 4, following the CQE Scoring Document.

Passed consensus evaluation

  • CodeJitsu - CB1
  • CSDS - CB1
  • DeepRed - CB1
  • Disekt - CB1
  • ForAllSecure - CB1
  • FuzzBOMB - CB1
  • Shellphish - CB1
  • TECHx - CB1
  • TrailofBits - CB1

Proved a POV in reference challenge

Defense against reference POVs

  • ForAllSecure: 100.0% - CB1
  • TrailofBits: 100.0% - CB1
  • CSDS: 100.0% - CB1
  • DeepRed: 100.0% - CB1

No submission

  • Eighth Place Team
  • Eleventh Place Team
  • Fifth Place Team - Finalist
  • First Place Team - Finalist
  • Fourth Place Team - Finalist
  • Ninth Place Team
  • Second Place Team - Finalist
  • Seventh Place Team - Finalist
  • Sixth Place Team - Finalist
  • Tenth Place Team
  • Third Place Team - Finalist
  • Thirteenth Place Team
  • Twelfth Place Team

All Submissions

Author Information

"Ben Schmidt" info@narfindustries.com

DARPA performer group

Narf Industries (NRFIN)


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Feature List

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Integer overflow when uploading extremely compressed data, leading to heap corruption. These types of vulnerabilities are quite common in real-world compression libraries, and continue to be a problem today (see CVE-2014-4607 - 11).

To trigger the overflow, competitor PoV's must both add an overly compressed video and then play it with the proper key, causing it to actually be decompressed.

All uploaded videos are expected to be run-length encoded, xored with a static key (0x42), with a very simple checksum of the run-length encoded data pre-xor. This checksum, along with restrictive length requirements, should prevent attempts at blind fuzzing.

The overflow occurs when the resulting number of bytes from the decoding process is greater than 2^24 bytes, causing an overflow of the dlen variable, which is defined as a 24 bit bitfield. Only inputs that have a compression ratio of at least ~127:1 will both trigger the overflow and be small enough to pass a prior length check.

Generic class of vulnerability

Integer Overflow Buffer Overflow

CWE classification

CWE-680: Integer Overflow to Buffer Overflow


  • Understanding the transforms necessary to successfully generate correct, highly compressed data. This requires the successful computation of a simple checksum, understanding and using a simple xor encoder, and proper generation of run-length encoded data.
  • Utilizing primitive operations in decompression routine repeatedly to trigger overflow.
  • Detecting integer overflow vulnerabilities, specificially one in a 3 byte bitfield.
  • Breaking our excellent DRM.

Curated by Lunge Technology, LLC. Questions or comments? Send us email