Malicious PDF — malware analysis report

Static analysis result for SHA-256 b67bf50a7113ffda…

MALICIOUS

PDF

65.4 KB Created: 2020-05-20 02:48:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 64b083b747063c16165683cfc8d3078d SHA-1: 6b14267199934de099bd0f90865a358e5cee6c65 SHA-256: b67bf50a7113ffda83a0f48f3b5e8b931d54048d851bb1551d7592f54b7fcbdc
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, a common tactic for SEO spam or redirecting users to malicious sites. The document body, though partially corrupted, contains text related to 'Rules of subject and verb agreement' and mentions 'wkhtmltopdf', suggesting it was generated programmatically to appear as a legitimate document. The presence of a large number of external PDF links points towards a link farm or a method to distribute further malicious content.

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://livingcheers.com/uploads/1/3/0/8/130873957/130873957.html#rules+of+subject+and+verb+agreement PDF link annotation
    • http://firstcoastcms.net/uploads/1/3/0/7/130776828/5498311.pdfIn PDF document text
    • http://transportlipigorski.pl/uploads/1/3/1/4/131406046/4130434.pdfIn PDF document text
    • http://perraulthouse.com/uploads/1/3/0/4/130476332/4651109.pdfIn PDF document text
    • http://elitemaintenancellc.net/uploads/1/3/0/6/130604595/vikob.pdfIn PDF document text
    • http://thisfancyyarn.com/uploads/1/3/1/6/131606968/xopotow.pdfIn PDF document text
    • http://epiclifestylemanagement.com/uploads/1/3/1/8/131856887/dakozukibomebikuzub.pdfIn PDF document text
    • http://apponagansettfarm.com/uploads/1/3/0/5/130588564/647f3fd78.pdfIn PDF document text
    • http://bfxblack.com/uploads/1/3/1/0/131070168/lusetuxo.pdfIn PDF document text
    • http://weilerandborst.com/uploads/1/3/0/5/130539315/zenojikebazufew.pdfIn PDF document text
    • http://reconmetal.ca/uploads/1/3/0/9/130968915/d97f6b.pdfIn PDF document text
    • http://adrianbyrdcounseling.com/uploads/1/3/0/4/130435844/5635766.pdfIn PDF document text
    • http://missmillersclassroom.com/uploads/1/3/1/4/131409861/df3fd0baad30.pdfIn PDF document text
    • http://avoid1800stranger.net/uploads/1/3/0/4/130490421/rogijikorudipe_fijaparuwewasof_tupidinu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67E 10424 bytes
SHA-256: 7bfd4ad161a87d54783f558f453d2bfa070541d24ea7e8133d383d2b8620539f