Malicious PDF — malware analysis report

Static analysis result for SHA-256 af3b2856097dd889…

MALICIOUS

PDF

41.0 KB Created: 2020-04-20 22:43:00 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: c70835b1622db1259273a0802bbd9f78 SHA-1: 91f3d8915c822a43d4936074863edd97ed3d26c4 SHA-256: af3b2856097dd88915af0bc855755d124e2a32c3c2d88ec7c8187f5244578bc9
94 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to domains that appear to be part of a link farm designed to artificially inflate search engine rankings. The primary URL, http://urfacefix.com/uploads/1/3/1/4/131408280/131408280.html, is presented with a lure of 'free alliteration worksheets for kindergarten'. This suggests a social engineering tactic to drive traffic to potentially malicious or phishing websites. The ML classifier strongly supports the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://urfacefix.com/uploads/1/3/1/4/131408280/131408280.html#free+alliteration+worksheets+for+kindergarten
    • http://bpgaragemaine.com/uploads/1/3/1/4/131438888/zuruxeza.pdf
    • http://naturquita.es/uploads/1/3/1/4/131452817/wivuvebubep.pdf
    • http://ugomicci.it/uploads/1/3/0/9/130969563/fbe85f.pdf
    • http://lifeofcheer.com/uploads/1/3/1/4/131438156/pewozuzelofoxuzejudo.pdf
    • http://wholewomansymposium.com/uploads/1/3/0/4/130483256/vinawexezapo-bomenozud-dajamu.pdf
    • http://idtvactionfest.com/uploads/1/3/0/4/130476012/wibepajepebeku.pdf
    • http://un-mariage-a-la-reunion.fr/uploads/1/3/0/5/130590509/bawojagunuwa_rexafeti_bojar.pdf
    • http://bpdsurf.com/uploads/1/3/0/7/130776046/2986f6195082.pdf
    • http://qodelive.com/uploads/1/3/0/6/130603928/goxuxezivizof.pdf
    • http://wholewomansymposium.com/uploads/1/3/0/4/130483256/vinawexezapo-bomenozud-dajamu.pd
    • 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_off0000780f.bin
f575aef66b12417e7551d28d8ce216c1d4a8c77f7cbaca7608ef9a687dd303c4		 pdf-font-stream PDF embedded font (sfnt) at offset 0x780F 8332 bytes

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