Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3e92d445f380812…

MALICIOUS

PDF

73.6 KB Created: 2021-09-27 09:02:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 51fb30f894c4c61b073a67f8b6c64bf8 SHA-1: f984cf9b47531a1003ab50ed161842d68a47717e SHA-256: f3e92d445f380812f5f58f926f2c96bf0f2c9ede6e371094c80c8bd6c5887b76
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded links, with one specifically identified as part of a link farm hosted on disposable domains, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the heuristic firings strongly point towards a malicious PDF designed to redirect users to external, potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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 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 http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16150fbaf86152---nuxoxuposudefopomebe.pdf In PDF document text
    • https://branchennachweis.eu/userfiles/file/79137066452.pdfIn PDF document text
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/11381685727.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/dipilepini.pdfIn PDF document text
    • https://specialgarden.ro/userfiles/file/jagabaredabuge.pdfIn PDF document text
    • http://punaide.com/userfiles/files/wusadezemomafeluz.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/tavarufif.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090801272667.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/47175372753.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/a62cq6bdc19qr34a93phpqm36r/35866679105.pdfIn PDF document text
    • http://optykglowacki.pl/obrazki/files/35818702107.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/53806572373.pdfIn PDF document text
    • https://bselink.com/userfiles/file/bobabasepubib.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/nifalepedamozifak.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/xakakuwemi.pdfIn PDF document text
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/legusovirosusudi.pdfIn PDF document text
    • https://processwork.archerhuang.com/ConImg/files/89710454603.pdfIn PDF document text
    • http://ezclasssites.com/var/wwww/dev-ezclasssites-com/data/files/55627864319.pdfIn PDF document text
    • https://migger.dk/userimages/file/74483043957.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-8/20210908075747172197.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/sogav.pdfIn PDF document text
    • http://sk4education.com/ckfinder/userfiles/files/62542294404.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/98422877300.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/gimajanojasabex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=app+in+place+of+shareitPDF 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_off0000b7f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7F7 10560 bytes
SHA-256: 3b1690668de98fbdca1081a33c33a20dde2a62e73aeb3e35647e43683f282b76
font_01_sfnt_off0000d00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD00B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e81d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE81D 19108 bytes
SHA-256: f62fd270b6a0811d9b0168adb564592d6303797a86a9b9ec8c8461a4cb5853c1