Malicious PDF — malware analysis report

Static analysis result for SHA-256 5151167f9d195979…

MALICIOUS

PDF

44.3 KB Created: 2020-06-21 19:49:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 305f31a4cb0b34442ef6f93b3461e18c SHA-1: d474df13a94f0a33110510122b07d201603e4620 SHA-256: 5151167f9d19597929168b7a89e0fee06564c6144c35d8cfb99d3dcb99d66c68
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to other PDFs on similarly structured domains. This pattern is indicative of a link farm or redirection scheme designed to distribute malicious content. The ML classifier strongly supports the malicious verdict, and the PDF_SEO_LINK_FARM heuristic confirms the suspicious linking behavior.

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://simplicityinliving.com/uploads/1/3/0/3/130313158/130313158.html#monthly+goals+worksheet PDF link annotation
    • http://crispconnection.com/uploads/1/3/1/4/131406560/db8466e4.pdfIn PDF document text
    • http://resinartpainting.com/uploads/1/3/0/5/130590164/tetemimupi.pdfIn PDF document text
    • http://74-123-78-37.mgwnet.com/uploads/1/3/0/6/130604173/dovab-fubixeguxeta-vofuviz-xorij.pdfIn PDF document text
    • http://mta-sts.mx.okichitaw.com/uploads/1/3/0/3/130313224/3446875.pdfIn PDF document text
    • http://atlanta360marketing.com/uploads/1/3/0/2/130288924/7050448.pdfIn PDF document text
    • http://mta-sts.mail.stephencoxart.com/uploads/1/3/2/6/132696178/ed420e4.pdfIn PDF document text
    • http://brittany-bradford.com/uploads/1/3/0/7/130775167/bubevetokon_sobetox.pdfIn PDF document text
    • http://resurrectedreliques.com/uploads/1/3/0/5/130541211/7705196.pdfIn PDF document text
    • http://211.bpmtc.com/uploads/1/3/0/9/130969200/3bccfee795.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004f69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4F69 4952 bytes
SHA-256: 5e9d1af8cccaaec71d3f71ae26eb59aa775d51b2dda7842d8c56608bd2bd00de
font_01_sfnt_off00006049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6049 1800 bytes
SHA-256: d0fa2da35d6f3db94f9a941810d5dd278cca46e3fb3b20692c5c4b724776b87a
font_02_sfnt_off000068d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x68D8 10740 bytes
SHA-256: 268ac2bc4a85bfe1886489ee8aa5a7b0599a0f616383e449f37709454d53675d
font_03_sfnt_off00008db5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8DB5 16312 bytes
SHA-256: f6934ae2c95101ef60819358d1fb1465271273a8a1b9fa0a75e54201e41ce702