Malicious PDF — malware analysis report

Static analysis result for SHA-256 91dbb3f4143d1929…

MALICIOUS

PDF

78.3 KB Created: 2021-06-09 19:27:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: e4a1ef749e7a319e4f3947f0271a8bb2 SHA-1: 0a04352116206bcc30822f4ed8665599e891c335 SHA-256: 91dbb3f4143d19290bcf82178d47c16b69cf358ae898123b07cf1c1cb0dc7bc3
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 pointing to disposable hosting services, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the PDF structure itself facilitates the redirection to potentially harmful URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://pistant.ru/pbw?utm_term=uri+the+surgical+strike+full+movie PDF link annotation
    • https://jodexozemusokut.weebly.com/uploads/1/3/3/9/133999246/8413007.pdfIn PDF document text
    • https://jiwazakamofefuf.weebly.com/uploads/1/3/4/0/134041011/a2316.pdfIn PDF document text
    • https://depemazijibibo.weebly.com/uploads/1/3/4/8/134846300/55d7be1728cf878.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459636/normal_5ff16133ec2d5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4460678/normal_5fccc1992f50c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483855/normal_6047c0f4accb2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4494661/normal_5fc884a68c439.pdfIn PDF document text
    • https://jilorewiruladof.weebly.com/uploads/1/3/4/5/134595325/pezewekezet.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tejudafo.pbworks.com/f/vegekewerigoroxuvoze.pdfIn PDF document text
    • http://savavaze.pbworks.com/w/file/fetch/144470352/aratrma_inceleme_yoluyla_retim_stratejisi_rnek_ders_plan.pdfIn PDF document text
    • http://bokibagaror.pbworks.com/f/ventajas_y_desventajas_del_modelo_cero_defectos.pdfIn PDF document text
    • http://kukuwowuxen.pbworks.com/f/present_tense_worksheet_for_class_6.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a3afc31-8c4a-4b3b-9441-218564804114/introducing_phonetics_and_phonology.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/652aa676-b1da-43bb-92e4-30763254d4e3/dell_optiplex_9020_motherboard_specs.pdfIn PDF document text
    • http://gibuwodebu.pbworks.com/f/39393564180.pdfIn PDF document text
    • http://lulimogosan.pbworks.com/f/gabezivuvofefudizer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b956600e-495a-4257-906e-1c333df54036/vawogebirapexop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/315cbf12-801d-4d0b-a724-58375c280d62/how_to_program_433mhz_remote.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0ab49045-fb63-475b-9575-5942a4284cb4/vasibatavubosevonibamu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e7bac75c-c57e-4c9d-93d0-e17e656f8fd8/23238086628.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/85684846-3a8d-405b-99f4-5ad817b43d0a/the_walking_dead_compendium_download.pdfIn PDF document text
    • http://sujagajo.pbworks.com/f/refojimokifufizetir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6fe7a97-3685-41ad-9b5a-200f02933548/88527707009.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3646d7b2-0585-4cc1-a6b1-9bb0fa255f1a/7867164253.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_off0000da9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA9C 5408 bytes
SHA-256: a778c78531bd9ccf4adebd2312154b05b51f835d4ffc81e7230246fa0bfef491
font_01_sfnt_off0000ecee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEE 12948 bytes
SHA-256: f7583172d4d4144c97b2df040b36242629c7a57d373b3b2dda1796874bc9ed43
font_02_sfnt_off0001143f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1143F 16192 bytes
SHA-256: 4682b72f2afa33b20cf875d84024ffdd6778cb348d5560ed491e7fe37e149525