Malicious PDF — malware analysis report

Static analysis result for SHA-256 833f0162eb5a35db…

MALICIOUS

PDF

73.3 KB Created: 2021-03-11 17:15:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: d51ee9ffadaf9ad9f419150a382139eb SHA-1: d989e2373f85b8b2060af6c4e076961ef135db92 SHA-256: 833f0162eb5a35db18ab3d3101d0cc29ead7a875d836f554c97fb3fd7b9a90f9
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or phishing operation. The primary URL, 'https://baarspo.ru/wix?keyword=endocrine+system+diagram+quiz', is likely a lure to direct users to malicious content or to gather information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://baarspo.ru/wix?keyword=endocrine+system+diagram+quiz PDF link annotation
    • http://posiriwase.22web.org/game_theory_nptel.pdfIn PDF document text
    • https://rejukikigukaw.weebly.com/uploads/1/3/5/3/135387704/tonosagurosuse.pdfIn PDF document text
    • https://janejamav.weebly.com/uploads/1/3/4/8/134887015/mamerurupon.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://6d4a8fb0-9a8a-4850-8aa1-2b5706121c9a.filesusr.com/ugd/ff2e72_490b93e18f074a039df3927607ef33ed.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ebd63528-a10a-4800-81ec-22832d069c83/ginezeminewaduke.pdfIn PDF document text
    • http://lijifenesur.epizy.com/14569902952.pdfIn PDF document text
    • https://e3e1c2aa-7f41-47b0-8c2f-d823cb48b857.filesusr.com/ugd/7598fa_4e322a8fd81343239f43db948cc23978.pdf?index=trueIn PDF document text
    • https://9610c43f-1b2a-4a8a-b660-75aaf3908198.filesusr.com/ugd/286fb8_657d0d9c4e1f47a399ff579190c9a7a1.pdf?index=trueIn PDF document text
    • https://858e1da1-ad31-4e5b-aec0-89c59c6c71f6.filesusr.com/ugd/6240f8_c3240a0fb26544e49ab10304c8dc53df.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a4d8cac-5fea-41b1-832a-45b6564b245f/lilobidajazedevi.pdfIn PDF document text
    • http://gofekujapi.rf.gd/23668529371.pdfIn PDF document text
    • https://16e729f2-8c5c-4787-b670-14aeba6c5e03.filesusr.com/ugd/ac55e2_1df0cecaef2d4ba9abf1d63c03f7c117.pdf?index=trueIn PDF document text
    • http://repeputowuz.epizy.com/arjun_classes_physics_notes.pdfIn PDF document text
    • http://novozozoto.epizy.com/66204538926.pdfIn PDF document text
    • https://b3dfd9c9-1030-471f-a26d-814ea73dbccc.filesusr.com/ugd/d97afa_05f8268afb894cd992a61187e0ce2c5e.pdf?index=trueIn PDF document text
    • https://dc58184e-bbba-402a-8e08-a55d552c8f3f.filesusr.com/ugd/0ebc1f_342752e7d8814371b5f5375789efb221.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/17fdd580-ad80-40d2-b99e-735ba006c251/a_simple_favor_book_sparknotes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0924e20f-a2b8-420d-8287-ffc36af258b2/loresibanununok.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7267b5d0-cf00-4d2c-bf18-fa80038a0896/line_6_firehawk_fx_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b94d6de0-ee2e-4359-9d83-cdf43da9d53e/honda_rancher_350_tire_size.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_off0000e10c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10C 5464 bytes
SHA-256: d6c09052889f870b580c3a15245eb632f1da41875d2861388581d9a2e48826a8
font_01_sfnt_off0000f393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF393 10704 bytes
SHA-256: f74608a5f2472b22eed21bb1c1729c2db010e1f12bf5baf989c7ff0e8bba2d7b