Malicious PDF — malware analysis report

Static analysis result for SHA-256 51d5880a7a158e23…

MALICIOUS

PDF

77.2 KB Created: 2021-03-18 17:25:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: d0f07353d76a8c94eb52e75541893a09 SHA-1: 54eb530680d4db1c582a01a391c187d9818e64d8 SHA-256: 51d5880a7a158e235ca0d565e82b97928959547d7bbd471b32c99323e85ac2d0
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many hosted on disposable domains, indicating a link farm designed for SEO manipulation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document intended to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://midufefew.ru/wix?keyword=nightmare+before+christmas+car+seat+covers+set PDF link annotation
    • https://cdn.sqhk.co/pafowijexube/tfAwrgi/crush_them_all_tier_list_2020_pve.pdfIn PDF document text
    • https://cdn.sqhk.co/mugapowejog/hgjdjhE/wefopixajidanumavuruzow.pdfIn PDF document text
    • http://pukegowavoja.iblogger.org/antisepticos_naturales.pdfIn PDF document text
    • https://cdn.sqhk.co/minofavazu/dxQLhaK/bucket_list_family_robbed_in_south_africa.pdfIn PDF document text
    • https://kowizonijate.weebly.com/uploads/1/3/5/9/135991151/bemowirijelif.pdfIn PDF document text
    • https://nofemifi.weebly.com/uploads/1/3/2/7/132710694/wokutorano.pdfIn PDF document text
    • https://cdn.sqhk.co/gozigawefo/lhebEib/elder_scrolls_skyrim_healing_potion_recipe.pdfIn PDF document text
    • https://wixoxane.weebly.com/uploads/1/3/4/7/134734379/puriw-wifozoperomo-sewemubo-zavajew.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/9580efbf-c98d-4e8b-adc9-71b788202df4/canto_el_pajaro_carpintero.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/93fe63cc-f72a-4a43-9e6c-43d4d5b7728d/is_the_fallout_series_overseers_desk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c41fd12-9ea8-4aa2-9dbf-fa709f9870aa/how_to_prepare_brownie_pan.pdfIn PDF document text
    • https://s3.amazonaws.com/viwoxuz/android_wear_iphone_battery.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f916481b-7362-4305-aafc-ff93fcaa7c38/wadupuniburaped.pdfIn PDF document text
    • https://s3.amazonaws.com/ladojenefe/greek_mythology_animated_movies.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b1c200f-507d-4d9a-9021-fdfc9a97a896/91911759255.pdfIn PDF document text
    • https://s3.amazonaws.com/gixirojozogufux/kevexaxaruwafefujefogimo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5927557d-1d86-41b9-9d11-8e7b1c4e7b80/mitonomafa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b5608a7-2cca-4896-afac-b078a84c4a1b/whirlpool_cabrio_platinum_washer_cycle_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97cee7f7-1b31-4db7-9d7e-231a6f0ea7ff/percy_jackson_sea_of_monsters_chapter_14_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab23900c-cd81-4360-9597-a6da21a58395/21137147642.pdfIn PDF document text
    • https://s3.amazonaws.com/jezobasit/rexorujinokikobegim.pdfIn PDF document text
    • https://s3.amazonaws.com/furunumaroxun/phonics_workbook_1.pdfIn PDF document text
    • http://wojodiguf.rf.gd/61427692944.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_off0000eea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA1 5432 bytes
SHA-256: 9a205feb813296f7bec40f8d86e8b4357b44e29e2837adc2b12f15e010b14d02
font_01_sfnt_off00010102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10102 11452 bytes
SHA-256: 50c3a18b0c1a1086eb5dc152a8ab9f2c6dd913232479d820f07af6ef08fbf2d1