Malicious PDF — malware analysis report

Static analysis result for SHA-256 27512cabfe50a9ce…

MALICIOUS

PDF

79.0 KB Created: 2021-09-17 13:55:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a411465a96a4eca666fedc727c835f32 SHA-1: a630dc604222c2a3a70009bd17d6fc6a5748ef54 SHA-256: 27512cabfe50a9ceb348d4e4fdc96c9376aa40b6db615a3aee73b120c7040a6a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, one of which is associated with 'adb download for pc'. The presence of numerous embedded URLs and the PDF's structure suggest an attempt to redirect users to potentially harmful sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://bk.knu.ac.kr/ckfinder/userfiles/files/digipawelemi.pdf In PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/4fc5b9ed4c640f5855d2662ea9db66f0/saruvabo.pdfIn PDF document text
    • http://psystems.gr/Administrator/uploads/userpics/OutPostImages/files/soxatamonige.pdfIn PDF document text
    • http://ghefootmassage.com/fckeditor_userfiles/file/26369353625.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/vogenevelodunowifuw.pdfIn PDF document text
    • https://paeonia.ch/userfiles/files/tepigokuzogivoravi.pdfIn PDF document text
    • http://metabolit.ru/files/file/sogika.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/dijaxumejolaxasezo.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/lipekotijitawudimu.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/jizaxor.pdfIn PDF document text
    • http://paneldeconso.com/userfiles/file/8084450518.pdfIn PDF document text
    • http://yhbinternational.com/userfiles/file/22761726323.pdfIn PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/vudinikawoxejuzimu.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/8187494321.pdfIn PDF document text
    • http://jfe.hk/userfiles/33955098621.pdfIn PDF document text
    • https://ismart99.net/upload/files/73300910598.pdfIn PDF document text
    • http://baheth24cars.com/ckfinder/userfiles/files/74909504754.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134beb85c9f4---fivufutonixowukuwimifo.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/dusetedonapozutobibani.pdfIn PDF document text
    • https://discovercefalu.it/_data/images/file/2767686938.pdfIn PDF document text
    • http://wieswioska.pl/userfiles/file/tufakedokudatimo.pdfIn PDF document text
    • https://villamishkan.com/310renonew/front/images/files/29374865570.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=adb+download+for+pcPDF 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_off0000d0d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EC 10332 bytes
SHA-256: 53077b3989650ed7de5239f87209f6d71b01a843b833e1fb160f3615ea59469f
font_02_sfnt_off0001002a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1002A 18228 bytes
SHA-256: ad912690e57968dd760ea8aa2d3e7981507090647dfe71d130f877968028cb80