Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f4541b253ecd910…

MALICIOUS

PDF

77.0 KB Created: 2021-05-03 11:16:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 3b2ded756842e9620c4b8ff655532f10 SHA-1: 1371155fef655b2cf31bd1efabde8a18d644279e SHA-256: 1f4541b253ecd910ba508965f913b9a8d973ad1c19de3c735719359cc17ae640
226 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a fake browser/software-install lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://mezovuduw.ru/strik?utm_term=asus+realtek+audio+driver+windows+7+64+bit+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4453342/normal_6019dd10030d0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455198/normal_60413d3027c8f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371258/normal_605b45e0d360a.pdfIn PDF document text
    • https://jizojalagakamu.weebly.com/uploads/1/3/4/8/134886497/3140837.pdfIn PDF document text
    • http://bekusududiko.iblogger.org/kejenulesasusasi.pdfIn PDF document text
    • https://nokejulaju.weebly.com/uploads/1/3/4/6/134696540/xikepogojetem_xufasugoxewezut_lefefonuj.pdfIn PDF document text
    • http://sunny-web.ru/which_cloud_certification_is_best_for_net_developermvbcz.pdfIn PDF document text
    • https://xuduburuk.weebly.com/uploads/1/3/4/3/134323667/b26016bb6575b6.pdfIn PDF document text
    • https://rajerese.weebly.com/uploads/1/3/4/3/134387708/2e8168dff7925a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485696/normal_602c06aee6b2a.pdfIn PDF document text
    • http://bisaxozitidif.22web.org/balancing_chemical_equations_answers.pdfIn PDF document text
    • http://vivezotutune.iblogger.org/introduction_to_artificial_intelligence_download.pdfIn PDF document text
    • https://visopitolunew.weebly.com/uploads/1/3/1/4/131483219/f9abe396c72.pdfIn PDF document text
    • http://prequester.online/kusofexoxoluwqn59b.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/79987e5e-2a05-461e-be44-30e17353eb13/susafirotatunimef.pdfIn PDF document text
    • http://xamusewegelaru.rf.gd/88088950202.pdfIn PDF document text
    • https://9d1e48ad-bcd7-4831-9b7b-7108443a63b6.filesusr.com/ugd/136d07_441041b239ab4afab62e49c559b28768.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/41aee9be-0751-4c1a-ba62-6456705bc724/in_the_heights_trailer_music.pdfIn PDF document text
    • http://visobiwedixupip.rf.gd/68986588128.pdfIn PDF document text
    • https://1e16f6d7-285b-4488-bf07-d3e24ac90e20.filesusr.com/ugd/417718_c0eac388979d48899ffa8ab119d4d80c.pdf?index=trueIn PDF document text
    • https://9db8f275-5044-409a-aa1b-3306d9dda9bd.filesusr.com/ugd/361f4b_c5a91e70db2a4eb9ba7f9b3e0fdbdc82.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd22d2a4-b17f-48a9-9d71-b7150e6a6a8b/journal_entry_examples_learning_accounting_the_easy_way.pdfIn PDF document text
    • https://2ac56fc1-f7ee-4366-9cb2-1681469c68ee.filesusr.com/ugd/b914b5_4fe65a49d31b49d28db4ee14e0f8bb97.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf84910f-45c0-45b4-9a1a-2135dad0f52b/55477608699.pdfIn PDF document text
    • https://64b67c6e-fbbd-4787-add8-9ed3e274c95c.filesusr.com/ugd/eb6612_fdbeede3863c46029241521647cc1296.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/58930e99-1e47-4fa7-9f97-93d245170530/think_like_a_freak_audiobook.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_off0000ee8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8A 5488 bytes
SHA-256: 3a729b41d1a0c2442fa80f4845b7d4a9873a06fa8d673954505db72d7f4ffd2d
font_01_sfnt_off00010160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10160 10580 bytes
SHA-256: e935f80cdd70c20c85c2b73edf9c3005e7d86c96b2720110f70ed24ab3756d52