Malicious PDF — malware analysis report

Static analysis result for SHA-256 88751f9b51ce0681…

MALICIOUS

PDF

85.3 KB Created: 2021-09-17 03:57:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 23be10d48332b2e80c42a2345fdeada7 SHA-1: 810b23a66517861aff92f1a495a041af320e252c SHA-256: 88751f9b51ce0681aba83020de9a9d8d8a39acb9a0171999c5b88bfc59e23bec
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to external resources, suggesting a phishing or content-luring scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is part of a link farm on disposable hosting, likely to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • 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 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://www.padanguparduotuve.lt/ckfinder/userfiles/files/67580187463.pdf In PDF document text
    • http://peetersinstallatietechniek.nl/upload/files/64485495411.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/40075268497.pdfIn PDF document text
    • http://goref.ru/files/file/nobinokeribotukoribex.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/giloxizomapido.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210904072921_12tklt.pdfIn PDF document text
    • http://workcoop.org/fckeditor/userimages/file/20210902062653.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/jobula.pdfIn PDF document text
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/18373753678.pdfIn PDF document text
    • http://tw-tms.com/uploadpic/xw/files/71921112237.pdfIn PDF document text
    • http://techbis.pl/files/file/wivixifetifonupexuwu.pdfIn PDF document text
    • https://limadelimon.com/images/file/35051602677.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/79831349849.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210901215433.pdfIn PDF document text
    • http://guowangcable.com/d/files/gobokakoganenegor.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/ribaratenot.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/95d9b29d76733729f0c0c2075afd16ae/kepagabuxitixarubix.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/fusazigazebem.pdfIn PDF document text
    • http://123podkrovie.sk/editor_uploads/files/45244999467.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/xunawota.pdfIn PDF document text
    • http://servicedental.it/userfiles/files/kekepopevetiwafi.pdfIn PDF document text
    • http://kemmurad.com/webroot/img/files/dolopujapupafoka.pdfIn PDF document text
    • https://kopari.hu/files/file/kokojirufo.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/vosulivatoje.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/vemapijozawuzabemiga.pdfIn PDF document text
    • https://zniczekowalczyk.com/user_images/file/rewiper.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=harry+potter+series+download+in+englishPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10298 16764 bytes
SHA-256: 1053f72a4fb634812fb4ea38f78e586e29a437f2eaee2ceba67db67a7377a126
font_02_sfnt_off00012dfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DFA 10864 bytes
SHA-256: ec4918b867c31673bf1dcedee3ad0263dee9c89c5133a37fb61ba01fb8b9fc59