Malicious PDF — malware analysis report

Static analysis result for SHA-256 acfb6c7788893dfa…

MALICIOUS

PDF

80.9 KB Created: 2021-06-12 18:02:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1ce707574005463d0d9480075ed7cfb0 SHA-1: af500ebbd7466567be0465180b6ebe13bd0735db SHA-256: acfb6c7788893dfab47bcba3013971804bf2299d7c8e4cbce71117d061ed3fa0
186 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external links, many pointing to disposable hosting, and is flagged by ClamAV as Pdf.Phishing.Trojan. The ML classifier also strongly indicated maliciousness. The primary malicious activity appears to be directing users to a link farm, likely for further exploitation or phishing, rather than executing embedded scripts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://cructi.ru/pbw?utm_term=a+manual+of+style+for+contract+drafting+fourth+edition+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4458150/normal_603f3d2abc5df.pdfIn PDF document text
    • https://xesusufekab.weebly.com/uploads/1/3/4/8/134864027/favilazodegolifasije.pdfIn PDF document text
    • https://besugadofozoxi.weebly.com/uploads/1/3/5/3/135396803/povejuwinuwuza.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451930/normal_5fd13fa26c5e4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403938/normal_6005cb373f85a.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/abd4e84a-c9ba-48ef-b0fe-ff67c1a3ac0e/46348445563.pdfIn PDF document text
    • http://garigor.pbworks.com/w/file/fetch/144425124/95684169747.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/288102a3-e3b5-4dad-a002-73512edeb33a/does_bleaching_cream_work_on_scars.pdfIn PDF document text
    • http://marutipug.pbworks.com/f/she_unnames_them.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c8feb54-3db7-4328-8fef-31ef7fbf3c9f/99948961672.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c7606c5-c217-442e-96b8-ff7f1f1c7f1f/2135380750.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/494cf170-94e5-4fd3-80ec-07ab49021cfa/palifusa.pdfIn PDF document text
    • http://sakulibur.pbworks.com/f/zuwixatadus.pdfIn PDF document text
    • http://jebodigezev.pbworks.com/w/file/fetch/145061742/the_horcrux_and_the_hand_lego_harry_potter_walkthrough.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1196178e-4bf1-416d-b4af-b78cc05c3479/how_to_pass_nyc_permit_test.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c297734-101d-4839-a9e1-a6366459ee15/gazizuso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c36775d-42c4-49a4-ae6c-7d9d77ba96ad/bobs_burgers_seaplane_transcript.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ff58192-c1b4-4a0f-9b35-f7e6956db577/how_to_reset_a_rinnai_hot_water_heater.pdfIn PDF document text
    • http://gexufak.pbworks.com/f/what_is_learner-centered_approach.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/531c3c41-630d-4dd1-8eb0-ed986c8b4aae/witcher_3_blood_and_wine_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/039d409d-b46f-4384-9c58-762471e21b5e/aashiqui_2_full_movie_hd_1080p_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa8aa801-6ff3-4b2d-85a3-3c8ee3a08ed2/17442423875.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD11 5660 bytes
SHA-256: aa79ab1ab28a21f1b91a6d28492ac2fe649bc42dad422dfdc8bc7ce767fba5e2
font_01_sfnt_off00011030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11030 10764 bytes
SHA-256: b89748e71d3448976f86f0318d4af262012790b88183fe4e1e72c6b5a1f9ee48