Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3baae81abb18ca6…

MALICIOUS

PDF

84.1 KB Created: 2021-05-28 17:26:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 69730021024db839d4461ce1600d5166 SHA-1: aa5badfa22c5af2df48ad1643e968be336881455 SHA-256: a3baae81abb18ca6758c6ec47f46264123e8c9ad3d3be18cd2bc432db00547dc
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, identified as a link farm designed to redirect users to potentially malicious sites. Heuristics like 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicate this malicious intent. The ClamAV detection and ML classifier further support the malicious nature of the file, pointing towards a phishing or malware distribution scheme.

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://vilenefex.ru/123?utm_term=sda+church+beliefs+pdf PDF link annotation
    • https://mitemulesebiped.weebly.com/uploads/1/3/4/4/134479511/vizizagutemig-wubowufofeje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422908/normal_60565848dcca1.pdfIn PDF document text
    • https://bonagimeduvutup.weebly.com/uploads/1/3/1/4/131453121/vapigokomavakizu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418192/normal_602cf9407c477.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448556/normal_602f6bf7deacb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369304/normal_5fd3a711b5757.pdfIn PDF document text
    • https://tarakemutelomul.weebly.com/uploads/1/3/2/3/132303353/mogitowogoxu_nizotojirodok.pdfIn PDF document text
    • https://fegikunula.weebly.com/uploads/1/3/4/4/134482285/nuzidukefewalexe.pdfIn PDF document text
    • https://xazujojupise.weebly.com/uploads/1/3/4/4/134493550/sunudogelerejufevar.pdfIn PDF document text
    • https://vefoduga.weebly.com/uploads/1/3/5/3/135302220/2341295.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366654/normal_60526916ec753.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495246/normal_600a76f413cef.pdfIn PDF document text
    • https://xulisonifob.weebly.com/uploads/1/3/2/6/132695361/4897290.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/7fa4c210-c6b1-4f82-9bba-1ec352569a55/19674550435.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5bca9d84-b7c2-42a5-ad5d-c0cbacd298fc/what_books_do_medical_students_use.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54caec1b-2ae5-4c0b-bf39-78bead2b5ad2/molecular_and_cellular_biology_jobs_uk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3bde103e-3a65-44e1-bd9e-9b9272008122/star_trek_battleship_game.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d809fbf3-52ea-4244-9d00-55c07c01710f/what_is_considered_sin_in_the_new_testament.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/02937b4b-3707-4685-b8f0-9708e8ee9e0b/learn_hindi_to_english_app.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/998de7c9-ccd9-44e3-8dd3-48875433083c/52660156957.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2295d18d-d4c0-4b7d-b18c-dbf84f15b250/bopudamuvezav.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_off0000f432.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF432 5488 bytes
SHA-256: dac9c3e8e7e2eea4de790bf9dd48b2ce76cc1d8e3afbdb33b6dcfa17ee7ebf15
font_01_sfnt_off000106ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CE 11396 bytes
SHA-256: 3a0436055e3eec788df9f9575d6c2a6d0cdad52d6f635abdbe3e018c3bba6b5f
font_02_sfnt_off00012db7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB7 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e