Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f987abf0b008a84…

MALICIOUS

PDF

77.8 KB Created: 2021-05-06 08:37:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 4723a7dd76c10007da7e018baa4b6033 SHA-1: 9cfc29fdb64a7b652efedf43500d3c42629a16d4 SHA-256: 3f987abf0b008a8492db6e81505867e280260ae7908e64cd79fbe895ccd95ff8
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and link farms, suggests a phishing or malware distribution scheme. The document body, though heavily obfuscated, contains references to wkhtmltopdf and Qt, potentially indicating a tool used to generate malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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://soxebez.ru/strik?utm_term=bowflex+pr1000+exercises+chart PDF link annotation
    • https://cdn.sqhk.co/kovixileta/XihMtV1/prestonplayz_minecraft_skin.pdfIn PDF document text
    • https://cdn.sqhk.co/fukonovum/gQaUiey/battle_souls_mod_apk_unlimited_money.pdfIn PDF document text
    • http://nosinoski.shop/sofewumezagadelipijugs08g.pdfIn PDF document text
    • http://tihefers.online/13437116205w7jbs.pdfIn PDF document text
    • https://fanevatonalusi.weebly.com/uploads/1/3/1/6/131637928/jenuloridozivafawi.pdfIn PDF document text
    • https://cdn.sqhk.co/bowazeduz/hhhjdD2/define_stumble_in_the_bible.pdfIn PDF document text
    • https://xuvasilibozin.weebly.com/uploads/1/3/5/3/135335949/vodiginifovifudimax.pdfIn PDF document text
    • https://vuwejugo.weebly.com/uploads/1/3/4/3/134309576/ruxizoluvuvuti.pdfIn PDF document text
    • http://about-central.com/75313527200lulb7.pdfIn PDF document text
    • http://bettyloustintruckbbq.com/verizon_smart_family_premium_location_servicesm5ff2.pdfIn PDF document text
    • https://sufusaripowo.weebly.com/uploads/1/3/1/4/131437865/8c7143e1baea7f6.pdfIn PDF document text
    • http://vukabuv.22web.org/acquisition_strategy_template_dod.pdfIn PDF document text
    • https://cdn.sqhk.co/fimegasaz/3uhibTF/real_steel_boxing_champions_mod_apk_revdl.pdfIn PDF document text
    • https://vulemozebo.weebly.com/uploads/1/3/4/6/134693025/mizovu-xuterupiz.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/48d94957-45b9-4c32-b53e-71d4996a0cba/mitchell_repair_center_download.pdfIn PDF document text
    • https://s3.amazonaws.com/wexukufedepim/challenge_bengali_full_movie_mkv.pdfIn PDF document text
    • https://s3.amazonaws.com/gimufesajo/line_6_ux2_install_on_mac.pdfIn PDF document text
    • https://s3.amazonaws.com/sixenogafopoj/90914585189.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1f777aef-7fbe-427b-8d6f-76b8890e142d/gozozutobavajakuwiwafile.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d736538c-e338-4834-bdeb-21754f9b63b5/56507081252.pdfIn PDF document text
    • http://kakuver.rf.gd/biografia_del_poder_caudillos_de_la_revolucion_mexicana.pdfIn PDF document text
    • https://s3.amazonaws.com/gadumagabusodel/9489801509.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_off0000f15c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15C 5508 bytes
SHA-256: d0cb7e66c710942f7cc0c31f893d12a13ea3586e8bb3fb0f4449494a3264297d
font_01_sfnt_off00010435.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10435 10540 bytes
SHA-256: 1ed5c0fc3ced95e93a551c0938d15a887661ffebf8022ad624d75bf49251dccd