Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0faffc70a230ac1…

MALICIOUS

PDF

70.8 KB Created: 2021-10-02 12:33:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 73576e2d62f0caa041ef777f6c1511a2 SHA-1: 2b625d3ec222fad5fbf946a87f4afb2a912e1d39 SHA-256: b0faffc70a230ac1ee97878fd53af363bdf363dad4d5e8deccb403c094efa137
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it's a link farm on disposable hosting. The PDF contains numerous embedded URLs pointing to external resources, suggesting a phishing or malware distribution lure. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest an attempt to redirect users to malicious sites.

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 https://laborke.ru/uplcv?utm_term=power+up+2+pupil%27s+book PDF link annotation
    • http://budgettranslation.hu/sites/default/files/file/moralesubimifefuvan.pdfIn PDF document text
    • https://harteron.ee/userfiles/file/woledetabapuga.pdfIn PDF document text
    • https://gifarlcm.com/upfiles/editor/files/47162241359.pdfIn PDF document text
    • https://franciscovalles.comtraining.cl/userfiles/files/83019532776.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/tiwivuku.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/xetobabiji.pdfIn PDF document text
    • http://honghuibio.com/d/files/47208264329.pdfIn PDF document text
    • http://beta-rc.com/upload/files/14725722957.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/5901996267.pdfIn PDF document text
    • http://itaxabc.com/userfiles/file/20210912031018_1911252506.pdfIn PDF document text
    • http://skolky.info/foto/images/file/gifamazurefamukiv.pdfIn PDF document text
    • https://yakin-surewin.com/media/file/nopomuviz.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/77068251457.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/fe411d11a2b0dbca43884c1ac1f861b6/pixenowivabelutamumajik.pdfIn PDF document text
    • http://debseven.net/UserFiles/File/rifetexadalorile.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/rominaxilerew.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/vabekuxoneludot.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/175061236130e65e14797.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/54432910171.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210910_12B7E1E26689644D.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/68314515351.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/peziriwatomamupawuzo.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/visesir.pdfIn PDF document text
    • https://icbacademy.com/upload/files/59978839718.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_off0000b083.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB083 17776 bytes
SHA-256: ae181254ae3f14d729eaad4a3690d63d554b24e908d362f81edf64640c40a512
font_01_sfnt_off0000ddbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D6 10456 bytes
SHA-256: c49762228dafcce095939e8d5c7fd94248d19f6f0112e20471388ba883e05a56