Malicious PDF — malware analysis report

Static analysis result for SHA-256 822571a1f6d9b32e…

MALICIOUS

PDF

79.6 KB Created: 2021-09-19 12:03:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 889206cf89e84cb9ed196770b237d4c3 SHA-1: cc57ac334c583c72b44dbbc495d09497c4d62ca8 SHA-256: 822571a1f6d9b32e8d84be0e92d2735fbf7ba3930ed164eff3c7ab1d505821d8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The PDF contains numerous embedded URLs pointing to external documents, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with spearphishing attachments designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://aiwcecckolkata.org/FCKeditor/file/maniw.pdf In PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/21244936293.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/belemiwofulunobewijezake.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/rakavedeleziv.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/4634139825.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/58335730468.pdfIn PDF document text
    • https://riondene.ch/img/uploads/file/ziwuraropelakew.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1614472269fd9c---93271802353.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210918230138.pdfIn PDF document text
    • http://craftland.de/res/wysiwyg/file/ziwuwuworuvig.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/sabinolivadadar.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/tukuja.pdfIn PDF document text
    • https://diphong.com/uploads/zikatimegudefunid.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/ledav.pdfIn PDF document text
    • http://alptw.com/images/files/limum.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134773548c74---88654093436.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/xuxevumapawodiziwejuwa.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/nufazoxopu.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/18743734901.pdfIn PDF document text
    • https://lazerom.pro/media/file/wurawupaferixejom.pdfIn PDF document text
    • https://jager-ig.tw/up_photo/file/davubinufipuruno.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/21905844003.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/jewezujuvukarudixezo.pdfIn PDF document text
    • http://embody.box8websites.com/ckfinder/userfiles/files/8885241454.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=hotspot+android+11PDF 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_off0000d48f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA6 10248 bytes
SHA-256: 97b0cf274dbc86a327c67bb11e8ac4dfc0d91926d12b6a4bd51d831a54d52958
font_02_sfnt_off000103c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C2 17544 bytes
SHA-256: a46b3359f710fc9e6d5ece8921799e34d4dbc1abb1f6b98086368e559c92b04c