Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5f16c9e8f23e16e…

MALICIOUS

PDF

35.4 KB Created: 2020-05-15 04:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-07-24
MD5: ad96f8162752c6750beec788beb9faf0 SHA-1: e26213714470d4dfee220c539582ae108de44234 SHA-256: a5f16c9e8f23e16e39bbfb3be930db3f593a6a12f8f801049f6314cc1cde1d03
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a large number of external links to various domains, indicating a link farm or SEO spamming operation. The ML classifier strongly flagged this PDF as malicious. The document body contains garbled text but also includes the URL http://thedressrules.com/uploads/1/3/0/8/130874262/130874262.html#cute+girl+dog+names+yahoo+answers, which is also present in the extracted URLs. No scripts were extracted from this sample.

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://thedressrules.com/uploads/1/3/0/8/130874262/130874262.html#cute+girl+dog+names+yahoo+answers PDF link annotation
    • http://semajclothing.com/uploads/1/3/0/8/130813696/nerukixaraje.pdfIn PDF document text
    • http://v3accounting.com/uploads/1/3/1/3/131379029/b05a337eac01a45.pdfIn PDF document text
    • http://jaggedhorizonknives.com/uploads/1/3/0/7/130775698/4981753.pdfIn PDF document text
    • http://maywoodkennels.com/uploads/1/3/1/6/131636839/bovituzu-befalojox-sezizasuganozu-niwetelugeku.pdfIn PDF document text
    • http://interior-essence.com/uploads/1/3/1/4/131438324/saruxutot_meniwefu_sigijadipoveved_lavarebepanuwef.pdfIn PDF document text
    • http://loveonwheelshs.com/uploads/1/3/0/5/130544230/afe1ca21cfd1.pdfIn PDF document text
    • http://newsolitude.org/uploads/1/3/1/4/131406659/173fea627c8ab3.pdfIn PDF document text
    • http://rebecca-a-johnson.com/uploads/1/3/0/4/130477287/b2bcd1c5f21a14b.pdfIn PDF document text
    • http://kennesawproperties.net/uploads/1/3/0/5/130552017/nenimusem.pdfIn PDF document text
    • http://tayloredsolutionsgroup.com/uploads/1/3/1/4/131438622/6132198.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005527.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5527 2900 bytes
SHA-256: 68d094faf81d2ea9f62e68ee4e789e40b6192f27e323b9e50c58fbaa8f881837
font_01_sfnt_off00005f65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F65 10404 bytes
SHA-256: 1806447ae8181f8bee4df7b2727082f1205bbff244c458fe4918013673460439