Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa168dd0d912f37…

MALICIOUS

PDF

68.6 KB Created: 2021-09-21 13:18:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e2cc7f0ff899c14efe8fdb518fe9b3e0 SHA-1: 13eb47e6034ce25aa6bb6b28c03b5ef6b23a4b20 SHA-256: efa168dd0d912f37bd35571412cb113066a7c7e9c59b00eea63ea6dcb760c01d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF 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 numerous disposable domains, which is a common tactic for phishing or distributing further malware. The presence of many unknown URLs supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://tonthephunglan.vn/upload/files/17409265357.pdf In PDF document text
    • https://privatecambodiatour.com/userfiles/file/29548428806.pdfIn PDF document text
    • https://100tmt.com/uploadimage/files/20210913150629.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/woropilodupanuxi.pdfIn PDF document text
    • http://malerbetrieb-malanders.de/Webseite/pics/fotos/1/file/saputofewulerin.pdfIn PDF document text
    • https://ladida.asia/sporlegen/administrator/imagetempfile/kasafurotudo.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210911133254.pdfIn PDF document text
    • http://ibrahimabuomira.com/ckeditor/ckfinder/userfiles/files/61244957939.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/87709062733.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/9687d6a1250de34933ffdad11dda613a/nakawobadapejefu.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/53243450607.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/34526607823.pdfIn PDF document text
    • http://toflight.mobi/attachment/ckeditor/files/309b65a91f6745fe65a9c63fbdd3097f.pdfIn PDF document text
    • http://laboratorioshamalab.com/userfiles/file/vixopewaforuwatodan.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/65882876647.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/19532632982.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210917093147.pdfIn PDF document text
    • http://lamgi.pl/ckfinder/userfiles/files/kalivevazele.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/sofusepelebonajenaji.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138ad35b69d8---27504665910.pdfIn PDF document text
    • http://climtech.com/files/files/89470177216.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.excore.hu/ckfinder/userfiles/files/79227292118.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=9apps+android+apkPDF 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_off0000b060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB060 15032 bytes
SHA-256: eb12a7d4e905d56b1386370beca1d77b708b1e961a098261f7f1e58460e52f8e
font_01_sfnt_off0000d5de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000edf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF5 10272 bytes
SHA-256: e1204618d84da09e3dba4635bc6a2accd98568da659824a9477136cf079260d8