Malicious PDF — malware analysis report

Static analysis result for SHA-256 df88ad4d27849198…

MALICIOUS

PDF

85.9 KB Created: 2021-03-22 23:16:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: c95b62a6081275ee766d0402f08b3501 SHA-1: e1629d3e37ef60ae180d9b93bf5de0b616e1b8db SHA-256: df88ad4d278491986260bca1d3a2896aed38376e10d6542d6ba98d102f3b6acf
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a large number of external links, many of which point to disposable domains, indicating a link farm designed to drive traffic or host malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 https://nipisod.ru/wix?keyword=screen+recorder+apk+download+without+watermark PDF link annotation
    • https://cdn.sqhk.co/vefobinibe/OigTIie/picskit_photo_editor_free_cutout_collage_filters.pdfIn PDF document text
    • https://cdn.sqhk.co/gabazumad/jiiggR7/22945448256.pdfIn PDF document text
    • http://tvoyoproc.fun/32883863024ag0tk.pdfIn PDF document text
    • https://lukawonudos.weebly.com/uploads/1/3/5/3/135320707/ca959206.pdfIn PDF document text
    • https://cdn.sqhk.co/wolebiduju/n2himIG/hidden_object_games_for_macbook.pdfIn PDF document text
    • https://votarozoxanobo.weebly.com/uploads/1/3/4/3/134315144/4282852.pdfIn PDF document text
    • https://cdn.sqhk.co/silijebutu/Qhfyiee/32063676194.pdfIn PDF document text
    • http://momentshop.website/allpowers_100w_18v_12v_solar_panelmrhs4.pdfIn PDF document text
    • http://trickyturkey.com/bostitch_f21pl_framing_nailer_revieww1qaw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://44879a12-c10a-431c-a98a-7de142752d0f.filesusr.com/ugd/bb4607_e25a524ff9d04adda8eb90e1040f561e.pdf?index=trueIn PDF document text
    • https://7043ee2c-bc2d-4d46-b82c-b0075177c1aa.filesusr.com/ugd/f862b5_647f40ec8b614a8caa1458183a2d9ec4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2cb1bc7-9581-4369-86d8-c9031c6536ea/74431222055.pdfIn PDF document text
    • https://237a2310-9536-43ad-add1-fe73b840a51a.filesusr.com/ugd/8b319d_37daa93fc18d454fb33a2dd62c2b875e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6edf7453-7efa-4418-aa02-1405cfdc081c/80214138944.pdfIn PDF document text
    • https://f1c0478e-57b3-422a-b8eb-433964b677d2.filesusr.com/ugd/16c17d_1728be44c1e141618f0c8bf4dec57174.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f77e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF77E 5396 bytes
SHA-256: 96ec53770ffd68763a5d6ef99e9196a3bb67f749c5c747936a74fd924368b689
font_01_sfnt_off000109c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C2 11252 bytes
SHA-256: e8183a3f271a40df97560cca2e520431da343c733103293f967ded862c266650
font_02_sfnt_off00013049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13049 17380 bytes
SHA-256: 1ddd9d4dd08e9ffd8101853470bfa517b3a9a800e6f076e96387aadee89e433d