Malicious PDF — malware analysis report

Static analysis result for SHA-256 77e43fb795db10a3…

MALICIOUS

PDF

99.0 KB Created: 2021-03-10 02:05:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 5cca19136cfa17dc39a4fd81f8e1958f SHA-1: 70f686b45020d97348841db68cf76bec1c6014b3 SHA-256: 77e43fb795db10a3454706e76e64d410810daf1241ef1c59e478e71e89352b8e
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to direct users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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/123?utm_term=bramblestar+nine+lives+ultimate+guide PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4461505/normal_600dba6ff1bb3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372074/normal_601ddcca6ecf2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4497110/normal_5fff7c9c504f4.pdfIn PDF document text
    • https://cdn.sqhk.co/mofokamibe/RJvibif/78948650984.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472484/normal_5fe24f4f3478d.pdfIn PDF document text
    • https://cdn.sqhk.co/nemanive/9IjghgZ/xemezepini.pdfIn PDF document text
    • https://cdn.sqhk.co/torazanopuni/dQIjaVS/light_ball_pokemon.pdfIn PDF document text
    • https://cdn.sqhk.co/xafileme/jc5icUy/anime_asagao_to_kase-_san.pdfIn PDF document text
    • https://cdn.sqhk.co/jasurisunav/awsFyEI/98164053555.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ed20371-03ce-4653-9ab2-f3bab7c17c88/morning_mood_song_in_movies.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/64e54214-70a1-4d35-b0a4-792332d4ac3c/c_programming_interview_questions_and_answers_with_explanation.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d416c3f1-539c-4ae5-9519-2a42a520e300/how_to_set_time_zone_on_marathon_atomic_clock.pdfIn PDF document text
    • https://181f3bdf-810f-4c34-abb3-9f3362228cd6.filesusr.com/ugd/30415f_24e5648df6b04a8ab81690fb2af21233.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a701b1f-532e-4255-a914-a9c1635f7aec/46027902751.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4cbd31b0-82a5-4bbf-8480-4edac8a97c10/how_to_get_cash_dividends_per_share.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5bf4fe0c-65e7-4f0d-bbb5-7b637decb53c/29836515496.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77d8c30f-fd96-47a9-bdb3-72f6152131f7/how_to_change_my_infrared_thermometer_back_to_fahrenheit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c91d7e3-c823-4d97-a191-4da2a3807876/libuwedozuribovo.pdfIn PDF document text
    • https://d4f4546a-a836-4b3d-8651-c56b89608eca.filesusr.com/ugd/3e9e83_b2c80e101cd64fb598569dad7a5f16d4.pdf?index=trueIn PDF document text
    • https://aa6d2f86-95e2-42cc-897e-6bbd71c3a116.filesusr.com/ugd/78daac_ffa49b2c64114210bc5ab32f474928ce.pdf?index=trueIn PDF document text
    • https://8fa10226-37c2-454d-bd65-ced70ecbf0c4.filesusr.com/ugd/c34aa9_707c1ead76fa437280b6f6d71ce85609.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/116487e7-28b4-4f26-8269-ed3d1716b609/world_hardest_maze_ever.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06074fcc-4743-4937-9fc2-a66c2b31c34a/islands_of_decolonial_love_stories__songs.pdfIn PDF document text
    • https://238a82c5-85a8-4641-a991-2f0f5270ddc4.filesusr.com/ugd/63f22d_38f56d57a8a04d2ba45e598846d56eb5.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013a4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A4A 2864 bytes
SHA-256: d9eb4a6120ea016b30114cb131a3221ed83c26ec4383e7d40e50d43a01dc9751
font_01_sfnt_off0001447c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1447C 5392 bytes
SHA-256: 9bf49030e15766125de30fd5b03e422b17034ae320e2bd836d770b72e4c5a942
font_02_sfnt_off000156be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156BE 11828 bytes
SHA-256: 3938796d4d3f416b64481058fe25a66ecc42a84808a35079396a4282dfc05eed