Malicious PDF — malware analysis report

Static analysis result for SHA-256 81983ccb3a6df070…

MALICIOUS

PDF

84.2 KB Created: 2021-04-05 02:54:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 346371c017c6cff6e6e3d4bb1bbd460a SHA-1: d3aa783f8bb4ce1511c6e73d397ae519d04f50d5 SHA-256: 81983ccb3a6df0704eb3de8640e36b97341bb714ec0ab5d8f65283c7f40c140b
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external URIs point towards a malicious document, potentially leveraging embedded JavaScript for further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://zajinet.ru/wix?keyword=lifetime+fitness+troy+open PDF link annotation
    • http://golomashvanna.xyz/hip_hop_drum_pads_experience_apk6kho7.pdfIn PDF document text
    • https://cdn.sqhk.co/zimopaji/j4DOP7f/virus_estomacales_tratamiento.pdfIn PDF document text
    • https://cdn.sqhk.co/gopuxipo/ajfkggd/hero_of_the_rails_games_free_online.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388050/normal_60223a658986c.pdfIn PDF document text
    • https://cdn.sqhk.co/tiwefuxab/mhihigd/sidezekudum.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451352/normal_5fc72b874b26e.pdfIn PDF document text
    • http://psychologyrelax.xyz/56729639866stom2.pdfIn PDF document text
    • https://cdn.sqhk.co/dufelogaruf/ghjdihJ/74735765208.pdfIn PDF document text
    • http://ig-about.net/seran_pandian_tamil_movie_songs_freepu6m5.pdfIn PDF document text
    • https://cdn.sqhk.co/wibepudib/ivEeijO/weak_matrix_organizational_structure_examples.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486535/normal_60119b3ca45e0.pdfIn PDF document text
    • http://b0xberry.online/xiripuvy3qhh.pdfIn PDF document text
    • https://pinosapop.weebly.com/uploads/1/3/4/1/134131344/sufuso.pdfIn PDF document text
    • http://tobaliwono.mygamesonline.org/fitafazefapa.pdfIn PDF document text
    • http://vittorguxx.site/88803276173gtvxo.pdfIn PDF document text
    • http://nakidki-alkantara.xyz/avaya_2420_phone_user_guidejsicv.pdfIn PDF document text
    • https://kuxadolawemigos.weebly.com/uploads/1/3/4/7/134712866/pepuzanivakel-dekatiduz-wazilexebov.pdfIn PDF document text
    • http://wonnaturila.space/57888276768bhs9s.pdfIn PDF document text
    • https://menusopam.weebly.com/uploads/1/3/4/5/134597334/7151459.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vogapodidojuguf.myartsonline.com/fokezifegapixuduwat.pdfIn PDF document text
    • http://tameladizikep.atwebpages.com/jileri.pdfIn PDF document text
    • http://vekisofekibote.myartsonline.com/pdf_adobe_acrobat_reader_9_free_download.pdfIn 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_off0000f747.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF747 4848 bytes
SHA-256: b6b9eea5957bafdcc49f6c52071d1a5e230955dda3c5d6cb3bebe4bdd59c56d7
font_01_sfnt_off000107c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C6 11380 bytes
SHA-256: 9f85d841e1b203deed17d0b1f018d0ff9ec0cb68b786db5df83bca97c89823da
font_02_sfnt_off00012de8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DE8 16176 bytes
SHA-256: a9f6f832ac6db2c07fedaded388bbbc825938349848724d68f73651b0518da36