Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ed8535cd4d86f58…

MALICIOUS

PDF

74.7 KB Created: 2021-03-09 22:40:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-13
MD5: 579c014520f7570870c243b09854235a SHA-1: 227c7aaa870c1fa2ee19cf10d2bd3923ddf034d7 SHA-256: 6ed8535cd4d86f581ea04cf37ace1e237df8f34c23d4c3956a297e3486f65e5c
186 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics as a link farm containing a large number of external URIs, with a critical alert for a mass external PDF link farm. The ML classifier and ClamAV also identified it as malicious. While no scripts were explicitly extracted, the presence of numerous external links suggests an attempt to redirect users to potentially malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://pelibifir.ru/award?keyword=copd+assessment+test+spanish+pdf PDF link annotation
    • https://genunilime.weebly.com/uploads/1/3/4/3/134344847/zepiwufiwubup.pdfIn PDF document text
    • http://adanakebap.org/359612531227bvk5.pdfIn PDF document text
    • https://worijuxadije.weebly.com/uploads/1/3/4/8/134863955/rijanalinumaze_wibesaxagi_wugapug.pdfIn PDF document text
    • http://upgrade4me.com/resif1gmos.pdfIn PDF document text
    • http://wozilimesiz.mypressonline.com/what_does_sum_up_mean_in_texting.pdfIn PDF document text
    • https://nelemiken.weebly.com/uploads/1/3/4/7/134704654/3744705.pdfIn PDF document text
    • http://filfex.ru/how_to_reset_counter_on_elkay_bottle_filler51tj1.pdfIn PDF document text
    • https://fetuxugov.weebly.com/uploads/1/3/4/6/134655394/4224e5eff.pdfIn PDF document text
    • https://kiziwovoxapi.weebly.com/uploads/1/3/4/6/134617524/xetedetato.pdfIn PDF document text
    • http://medebupima.sportsontheweb.net/is_a_link_between_worlds_a_remake_of_a_link_to_the_past.pdfIn PDF document text
    • https://sovanomi.weebly.com/uploads/1/3/5/3/135337195/62d9b.pdfIn PDF document text
    • https://wolapegod.weebly.com/uploads/1/3/0/7/130776073/138c679.pdfIn PDF document text
    • http://paxezimusosesa.scienceontheweb.net/letter_of_recommendation_for_assistant_principal.pdfIn PDF document text
    • https://kikafizujugu.weebly.com/uploads/1/3/4/0/134012642/6239383.pdfIn PDF document text
    • http://mugedly.xyz/213899752356uee2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://bigefen.rf.gd/14773770115.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3eab193-c79b-4473-9a8b-32d8e1bfe9a4/38774588482.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f47a5567-9aed-4c9b-8dcb-71de2f8993f1/mercruiser_4.3_alpha_one_engine_manual.pdfIn PDF document text
    • http://bukevixu.epizy.com/grohe_kitchen_tap_repair.pdfIn PDF document text
    • http://fudewisukot.rf.gd/canny_edge_detection_in_image_processing.pdfIn PDF document text
    • http://difobasa.rf.gd/how_do_i_pair_a_plantronics_bluetooth_to_my_iphone.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/33a64a2f-559e-45d5-8257-553947a231d4/how_to_develop_a_super_memory_masterclass.pdfIn PDF document text
    • http://fojosotum.myartsonline.com/how_to_download_codecs.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_off0000e81c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE81C 5060 bytes
SHA-256: 9c4d46fb84b2fca6b719cc092f24a8afdb919210ad82709b16fbf78ab6bf799a
font_01_sfnt_off0000f92d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92D 10748 bytes
SHA-256: d70fecc9bf07af7d6af43810d9b475d24290c00a7d0e3c6b18ebaa11f1e5c6e1