Malicious PDF — malware analysis report

Static analysis result for SHA-256 53414b1d0e4847fa…

MALICIOUS

PDF

61.3 KB Created: 2020-05-22 12:31:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 04a7ad2b54e778338b30727db287073e SHA-1: 62f41b3fbe3678b3cfd29226307172928b9b2ad8 SHA-256: 53414b1d0e4847fa8139e4679abc61b07402434e1c727b089c8c6d75530e1643
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to other PDF files with numeric slugs in their URLs. This pattern is indicative of a link farm designed to manipulate search engine results and drive traffic to potentially unwanted software or malicious sites. The presence of 'Advanced uninstaller pro' in the document body suggests a lure for software download. The ML classifier also flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9163

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://c76vx.bpmtc.com/uploads/1/3/1/3/131383943/131383943.html#advanced+uninstaller+pro PDF link annotation
    • http://petcostumesatetoile.com/uploads/1/3/0/4/130483140/guwuxinopon.pdfIn PDF document text
    • http://milegion-legacyrun.org/uploads/1/3/0/6/130621116/wudoguzidozejas.pdfIn PDF document text
    • http://osowskycapital.com/uploads/1/3/0/4/130483070/nitokagosepatufe.pdfIn PDF document text
    • http://racelocalva.com/uploads/1/3/0/5/130538949/7874601.pdfIn PDF document text
    • http://northridgeresort.com/uploads/1/3/0/7/130738841/zitikun.pdfIn PDF document text
    • http://gswcardservices.info/uploads/1/3/1/1/131164129/pabesabiposezu.pdfIn PDF document text
    • http://firstbytecoders.com/uploads/1/3/1/1/131164414/nisikixuw_kasepilelekamu_valudugovufele.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000b2ca.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xB2CA 32316 bytes
SHA-256: 4ac546dfb533b64e50ec1b4cbbb360f70c982a17654293ee527d8ba7844bd747
font_00_sfnt_off000090f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x90F8 9840 bytes
SHA-256: 28356205576ab19d3f8e1cade615a2dad27a0ea07e6e85cae49ecb91cda6ab64