Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e5462a941de3d2b…

MALICIOUS

PDF

47.4 KB Created: 2020-04-22 09:23:28 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-04
MD5: 699e9bdc17417bd5a59648c078e17a27 SHA-1: 1ab19d078b1ab060a497d027fab9025d8c3dab5a SHA-256: 9e5462a941de3d2b6e0deaa61476b8096601942aff36ece74d21718bf78ef685
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to other PDF files on various domains. The document body text suggests it is a worksheet, which is likely a lure to encourage users to click on the embedded links. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass external link farm, suggesting a malicious intent to manipulate search engine results or distribute malicious content through a network of seemingly innocuous documents. No scripts were extracted, limiting the analysis of direct payload delivery.

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://kalajarvenlomakyla.fi/uploads/1/3/1/4/131408224/131408224.html#invariable+nouns+worksheet PDF link annotation
    • http://wikiwakie.com/uploads/1/3/0/7/130738962/3e3a24d23b8b4c.pdfIn PDF document text
    • http://skyaeros.com/uploads/1/3/0/8/130813639/sawinawuwesewemaw.pdfIn PDF document text
    • http://mmastrorilliciv.com/uploads/1/3/0/5/130551366/6262713.pdfIn PDF document text
    • http://kingsspeechpathologyclinic.net/uploads/1/3/1/6/131606619/3027970.pdfIn PDF document text
    • http://iyildirim.com/uploads/1/3/1/4/131436981/7beb0b.pdfIn PDF document text
    • http://diametricsgroup.com/uploads/1/3/1/4/131454522/11f7810b57f2a8.pdfIn PDF document text
    • http://chengclinic.org/uploads/1/3/0/5/130539309/6989212.pdfIn PDF document text
    • http://coldspringscampresort.info/uploads/1/3/0/5/130539846/9e277.pdfIn PDF document text
    • http://thebrennermans.com/uploads/1/3/1/4/131453321/6476719.pdfIn PDF document text
    • http://wagnercottonwedding.com/uploads/1/3/0/7/130775342/zuratuwosuw-tupubipujuk.pdfIn PDF document text
    • http://maxineworthy.com/uploads/1/3/0/7/130775084/801f1aa8fcd4.pdfIn PDF document text
    • http://slantrobotics.com/uploads/1/3/0/7/130740462/saxebufo-nologa-difepujot-gilulexo.pdfIn PDF document text
    • http://beamersbuddies.org/uploads/1/3/1/4/131406013/fbdaa6a.pdfIn PDF document text
    • http://carpetcleaning719.com/uploads/1/3/0/5/130588484/8714527.pdfIn PDF document text
    • http://gastoniapestpros.com/uploads/1/3/0/7/130775241/cd4e97b.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
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000070f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x70F1 8508 bytes
SHA-256: d0ea697c51695354394f2dfc85fb0a0a70340c3fac764e01ba2ed2bd687b9253
font_01_sfnt_off000091de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x91DE 2652 bytes
SHA-256: e2f1373bf3d70a40ff4276a486f0a1d2d32154e4f45ad1243a44c3d3b7d91cea
font_02_sfnt_off00009b47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9B47 16208 bytes
SHA-256: 5f95318943fcfbd77322bbb5cad315370152876080c91ba93f69ac7a8b13a41a