Malicious PDF — malware analysis report

Static analysis result for SHA-256 c23a4505c9315c45…

MALICIOUS

PDF

75.9 KB Created: 2021-03-03 11:11:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 6141f0cfcc0bb80c5bd2ea40a981389e SHA-1: bb6fc86081061af372b29cd65aeb8f884fdf86f6 SHA-256: c23a4505c9315c459a20ab518ec6e97ff5c94f67ed9842e2c49d57d41968bea0
246 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF document is identified as a credential phishing lure impersonating Instagram. It contains a large number of external links, many hosted on disposable domains, designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving exploitation for client execution via embedded links or potentially obfuscated scripts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://kifeketefisub.weebly.com/uploads/1/3/5/3/135347095/7041217.pdf.
  • 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://ponafet.ru/award?keyword=guns+germs+and+steel+summary+prologue PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4473919/normal_5feb04d7b3476.pdfIn PDF document text
    • https://kifeketefisub.weebly.com/uploads/1/3/5/3/135347095/7041217.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476122/normal_6025995d80db7.pdfIn PDF document text
    • https://cdn.sqhk.co/xusawikorut/hbjfv5U/feviligi.pdfIn PDF document text
    • https://cdn.sqhk.co/rigidaluta/gYzAlhd/private_instagram_video_downloader_apk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477649/normal_6010fb58c4035.pdfIn PDF document text
    • https://tefajakitom.weebly.com/uploads/1/3/1/3/131378990/1562290.pdfIn PDF document text
    • http://tewatag.medianewsonline.com/gevufetofezeguvimugew.pdfIn PDF document text
    • https://ripukalogud.weebly.com/uploads/1/3/4/3/134391837/aacce1884f38.pdfIn PDF document text
    • https://muwalivom.weebly.com/uploads/1/3/2/6/132695892/romimemotunab-refilavulurele.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367922/normal_5ffa391c0edea.pdfIn PDF document text
    • https://cdn.sqhk.co/teforoke/iiWjeia/72329030182.pdfIn PDF document text
    • https://jinikegubu.weebly.com/uploads/1/3/4/8/134873825/42ce9cedd3.pdfIn PDF document text
    • https://gejodawutu.weebly.com/uploads/1/3/1/1/131164152/logivozewimedumu.pdfIn PDF document text
    • https://cdn.sqhk.co/mezutorixo/ibjddig/the_floor_is_lava_board_game_uk.pdfIn PDF document text
    • https://cdn.sqhk.co/mitajaso/Gifjhgf/zulabikofuxesaxivav.pdfIn PDF document text
    • https://cdn.sqhk.co/tuzevawu/cjcLvhh/santorini_grecia_hotel_all_inclusive.pdfIn PDF document text
    • https://cdn.sqhk.co/gufuluzibos/T9haHib/lefofasegenuma.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sutexuvidag.myartsonline.com/the_game_tv_show_season_4-9.pdfIn PDF document text
    • http://nejesezape.myartsonline.com/35824337505.pdfIn PDF document text
    • http://newemepakirid.myartsonline.com/samsung_top_load_washing_machine_error_code_ub.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_off0000ed49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED49 5412 bytes
SHA-256: 423b945ae25e24e9ae7c4440f8255532abcd63a7af729416c4cf043092c45c7e
font_01_sfnt_off0000ffa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFA4 10064 bytes
SHA-256: 7a511e1ad1309fb9e2ac3d847bf8d64d5eb2b0e168f28fb13e0e35d5ea426ce4