Malicious PDF — malware analysis report

Static analysis result for SHA-256 538d172b1ed85e35…

MALICIOUS

PDF

41.7 KB Created: 2020-03-09 04:18:21 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: c707ea81400a8659d74459677c1df33e SHA-1: 52f62f27581e35c4a459e5847a372f248dfb7e35 SHA-256: 538d172b1ed85e3521329e55825dfcb7921cf6f88aee5698ffd361dcaa96c120
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many of which point to seemingly unrelated PDF files hosted on various domains. The document body, though partially corrupted, suggests a lure related to educational worksheets. The heuristic 'PDF_SEO_LINK_FARM' indicates a deliberate attempt to create a link farm, likely to improve search engine ranking for malicious content or to distribute malware. The ML classifier strongly supports the malicious nature of this PDF.

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://3hyaz4.bdgct.com/uploads/1/3/0/4/130490378/130490378.html#adding+mixed+fractions+with+unlike+denominators+worksheet
    • http://secretingredientislove.com/uploads/1/3/0/7/130775520/vutemodedole-kewetuno.pdf
    • http://okanaganfarmfresh.com/uploads/1/3/0/5/130588999/dd2d82c.pdf
    • http://monteur-zimmer-gelsenkirchen.de/uploads/1/3/0/7/130775759/1b0b8.pdf
    • http://kbchomeservicesllc.com/uploads/1/3/0/8/130814112/b8993c858f07b.pdf
    • http://rottenapplebackpackers.com/uploads/1/3/0/6/130621485/1179563.pdf
    • http://bealegacybuilder.com/uploads/1/3/0/2/130270899/714784b5d66.pdf
    • http://universalizability.com/uploads/1/3/0/2/130271045/2173512.pdf
    • http://apartmentsbastion.com/uploads/1/3/0/3/130379389/funifagabetanuxo.pdf
    • http://alldolledup-dollclothes.com/uploads/1/3/0/5/130550895/9147315.pdf
    • http://lifted-home.com/uploads/1/3/0/5/130589122/3154e1549.pdf
    • http://twobobpoker.com/uploads/1/3/0/3/130313005/43eeac32.pdf
    • http://bharpermd.com/uploads/1/3/0/6/130603936/mufure.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_off00007b67.bin
8c0f6fb0325643f4a1aa42f20802ad3427b6b501a374a85d43eb48912cbc8e82		 pdf-font-stream PDF embedded font (sfnt) at offset 0x7B67 7660 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.