Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba9995c1a440cdb2…

MALICIOUS

PDF

69.9 KB Created: 2021-09-28 10:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c035bbf90a63f9c5ecc932222ba5c96e SHA-1: cea50f03be8989d2f50dbf566e8c3f2841b5595b SHA-256: ba9995c1a440cdb256260ddaa467a04f2ea3bbcaeb21ed28b319e14b0a4a741d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm on disposable hosting, containing numerous external URIs. The document body is heavily obfuscated, but the presence of embedded URLs and the link farm heuristic strongly suggest a phishing or malware distribution attempt.

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://cructi.ru/uplcv?utm_term=minecraft+redstone+house+ideas PDF link annotation
    • http://a-xian-coat.com/uploads/files/202109190150162845.pdfIn PDF document text
    • https://samsungklima.net/upload/ckfinder/files/zovijuxigi.pdfIn PDF document text
    • http://hrampetraipavlavosstanovlenie.ru/content/images/user/file/tikavokoxexefi.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/kefotexija.pdfIn PDF document text
    • http://captainkillmite.com/uploads/files/202109172154447428.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/22535083084.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/pamoziwoxada.pdfIn PDF document text
    • http://neoneofitou.com/ckfinder/userfiles/files/vusar.pdfIn PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/86754246152.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/lenuvoritojegiwide.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-02-23-05-03-41.pdfIn PDF document text
    • http://0048.pl/48files/file/jarofen.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/jozakon.pdfIn PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/31673013404.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/zovidokezasaxojebuwuwoz.pdfIn PDF document text
    • https://www.lipca.com/ckfinder/userfiles/files/35764284163.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/3075402289.pdfIn PDF document text
    • https://fasaac.org/temp/files/lubalaki.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614be532bc686---jozovomulapilipoxoza.pdfIn PDF document text
    • http://cke.hk/userfiles/bubezurutomevizikirivunax.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614dfc01403ad---34255421642.pdfIn PDF document text
    • http://fastcredit.ge/userfiles/file/zojobiratojosolefupe.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/23361493281.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/mitasavopubufozagof.pdfIn PDF document text
    • http://sensor4you.com/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/birununiputudu.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://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_off0000b0e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0E2 10620 bytes
SHA-256: 811b261bdc11dc89ca1b51728497f913e6d7936011b62d9aa054094dc36b777b
font_01_sfnt_off0000c924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC924 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e136.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE136 16008 bytes
SHA-256: a4595eba42eaa1e8ad39406e36ac907e1930855955e4763ac2a38e032f2a255b