Malicious PDF — malware analysis report

Static analysis result for SHA-256 7989b929cb582018…

MALICIOUS

PDF

39.4 KB Created: 2020-03-30 03:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 11dba4d9ad2c492446aaad2cf5dd9f2d SHA-1: 76dda74c9800a4eb3884ea0d5ad10a66e7d795c2 SHA-256: 7989b929cb5820183e24b035020f75dfd3e5b952f1979ed54133fdd0bd281d38
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Phishing:Spearphishing Attachment T1204.002 Malicious Link:Malicious File

The PDF document contains numerous external links, many of which point to PDF files hosted on domains that appear to be part of a link farm. The document body, though partially corrupted, contains a lure related to matrix inversion and references the wkhtmltopdf tool, suggesting it was generated programmatically. The ML classifier strongly indicated maliciousness, and the overall structure points to a campaign distributing content via SEO-optimized link farms, likely to host further malicious payloads or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://adsl-63-204-18-21.benefitplans.org/uploads/1/3/0/9/130969845/130969845.html#how+to+find+the+inverse+of+a+matrix+2x2
    • http://marileeparrish.com/uploads/1/3/0/7/130776861/ad426bc4d.pdf
    • http://nedasalmanpour.com/uploads/1/3/0/4/130476271/fc3dd0.pdf
    • http://thebrocbd.com/uploads/1/3/0/4/130489499/kosozajiwonufus_jusus_filunita.pdf
    • http://forgedinfire.ca/uploads/1/3/0/3/130324370/nodalorove.pdf
    • http://boattrailershouston.com/uploads/1/3/0/5/130588388/12d040c86b1c.pdf
    • http://chairssite.com/uploads/1/3/0/7/130776458/30b86fd1f63.pdf
    • http://socialrealestateclub.com/uploads/1/3/0/2/130287285/2812933.pdf
    • http://thekasasisters.com/uploads/1/3/0/5/130540063/8b876022.pdf
    • http://luminouswater.us/uploads/1/3/0/6/130604419/3d72f4ee1cba13c.pdf
    • http://medien-im-deutschunterricht.de/uploads/1/3/0/9/130969808/9052860.pdf
    • http://marketingtipsnow.com/uploads/1/3/0/4/130492771/9bcce.pdf
    • http://kammnevescottage.com/uploads/1/3/0/2/130288830/3c5ec23.pdf
    • http://otairving.com/uploads/1/3/0/8/130814769/milol.pdf
    • http://lisaderanekmd-for-medinacoroner.com/uploads/1/3/0/6/130639933/ketepabafomurajo.pdf
    • http://impulse-healing.com/uploads/1/3/0/6/130604516/goxifutubujepuxitolo.pdf
    • http://nataschawlotzka.com/uploads/1/3/0/5/130588687/futodewudimu-gegoxupimovura-joxemenokav-guropobulizexa.pdf
    • http://bebrandconfident.live/uploads/1/3/0/2/130272575/28bf39d5.pdf
    • http://vantagepointtravel.com/uploads/1/3/0/5/130588299/1083344.pdf
    • http://wickedfreshsalad.com/uploads/1/3/0/4/130489247/2364589.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006f36.bin
29789c4b433079aab89e9c2ce4f40b6e23e331de68d10675b12ffae1b4275779
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F36 8484 bytes