Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3906b10f2ff4a7e…

MALICIOUS

PDF

78.7 KB Created: 2021-03-31 01:56:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: b258d611dcb5dd6842c9add4cf9211cf SHA-1: 2c794b323d7beab342604012ecf401e2b1dade6b SHA-256: e3906b10f2ff4a7e0f3d0c825ca7a41aaf14a4fa6091ae00e3a18ceea8964ad8
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 or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via the linked URLs. No scripts were extracted, but the PDF structure and URL heuristics point to a malicious document.

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://jacksth.ru/strik?utm_term=hp+envy+4500+ink+compatible PDF link annotation
    • https://cdn.sqhk.co/josozudibud/giZgdno/49857835524.pdfIn PDF document text
    • https://cdn.sqhk.co/lofesaxudiwo/SU1fohg/solubility_of_group_2_sulphates_chemguide.pdfIn PDF document text
    • http://usersonlineguardingsettings.site/astm_a53_standard_free9j7gk.pdfIn PDF document text
    • http://avtoshtorki.shop/harry_potter_yla_camara_secreta_resumen_por_capituloso9pmv.pdfIn PDF document text
    • https://bokusisosi.weebly.com/uploads/1/3/0/7/130775109/vofamo.pdfIn PDF document text
    • https://lomimasexoguxi.weebly.com/uploads/1/3/4/7/134736135/be5028bd6.pdfIn PDF document text
    • https://mazokaru.weebly.com/uploads/1/3/5/3/135303974/575592c5c5e4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gateguka.epizy.com/chhota_bheem_and_krishna_cartoon.pdfIn PDF document text
    • https://eecb1da5-82b7-48ef-90e5-6a20895c07e7.filesusr.com/ugd/88a84f_26a4a1fe53bc4acb833a4a20975cf37f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/01062fcc-068d-4d15-947c-cc3625819d22/pioneer_avh-x3600bhs_manual.pdfIn PDF document text
    • https://e4da1597-3bb3-488b-9226-7c2c9e06e9ce.filesusr.com/ugd/db5d73_07800288f60d4e7097da5f6a79eb64f1.pdf?index=trueIn PDF document text
    • https://9387bd13-3746-4408-b474-2867f26e464d.filesusr.com/ugd/ace02d_c8f88e8cf0764809899828b6ced247e1.pdf?index=trueIn PDF document text
    • https://4c8e72c6-e2e3-4108-adc6-102de481692d.filesusr.com/ugd/f4b4ca_c76fe722d6dc4d178fbbc51a06c1dc03.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bbb1d00a-82a7-44d9-9898-c1413a0c6b8e/ssr_125_exhaust_upgrade.pdfIn PDF document text
    • http://nuzekifigusibu.rf.gd/nibepebenafetizebiguwosu.pdfIn PDF document text
    • https://a44a9d9e-3ce9-422e-9b5d-83ef2d4925cb.filesusr.com/ugd/3234e9_7b3652a8c10a4720ae1de632b482346f.pdf?index=trueIn PDF document text
    • http://tunowik.epizy.com/50909593060.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28e8cd85-9468-4385-b406-75f0faa2dfc7/subelisurimefakix.pdfIn PDF document text
    • http://rixejobol.epizy.com/modern_embroidery_designs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c848291f-424b-4a64-b586-58affa6e48cd/piforixijef.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36ba84db-a6e1-4e5f-8f71-9aad855546df/what_is_the_rational_planning_model.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_off0000f555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF555 5488 bytes
SHA-256: 1e8a64bddf9b8674037f6e38cab5068d40a0f88e2a40aaf8db7e5bd954528a7c
font_01_sfnt_off00010809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10809 11044 bytes
SHA-256: 3980388fdc09d86b189865249bcf8f8a1b876fb1550cbe3e5add30dc9aaad316