Malicious PDF — malware analysis report

Static analysis result for SHA-256 541f50f0ed9fdd30…

MALICIOUS

PDF

75.2 KB Created: 2021-10-15 21:16:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4860f9a46e56129ad39e270436e87c5a SHA-1: b6492cfad0289cd35b3358ff175b174b82fe48c3 SHA-256: 541f50f0ed9fdd3032039b51a23ca326a245c790df28da99324991ffbb904751
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous embedded URLs, many of which point to disposable hosting and are indicative of a phishing or link farm operation. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://catamma.ru/uplcv?utm_term=1st+puc+text+book+pdf PDF link annotation
    • http://ddservice-bmw.pl/userfiles/file/53275030881.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/siteniritinisiderobuvev.pdfIn PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/78999803318.pdfIn PDF document text
    • http://melly-incendie.fr/img_db/5115656209.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nisikekidasup.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/vupowe.pdfIn PDF document text
    • http://kietminhrivet.com/upload/files/35195456469.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/wuzabifumotove.pdfIn PDF document text
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/33004869342.pdfIn PDF document text
    • https://newline-eg.com/userfiles/file/kozij.pdfIn PDF document text
    • https://jills.reviewz.eu/app/webroot/files/userfiles/files/45194983891.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/99130114424.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/xuwuwajubapobuzu.pdfIn PDF document text
    • https://noticky.net/akce/fotky/file/23267694072.pdfIn PDF document text
    • https://grdr.org/paidel/ckfinder/userfiles/files/setosomagarefo.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/46710173365.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/15572786316.pdfIn PDF document text
    • http://ceramkgres.ru/userfiles/file/7122581687.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021100905343622.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16163e6c9e41bd---modaxofivol.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dizijiwogijudomewaxiz.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/5d922ad2e4863123c0557127a1dac707/32550755205.pdfIn PDF document text
    • https://hoavily.com/uploads/files/59177298903.pdfIn PDF document text
    • https://consultemergingmarkets.cubsindia.com/files/xoxagojuxodowemobapavu.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_off0000bf86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d798.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD798 18384 bytes
SHA-256: fbf4204221643aaa7609adf3c09455a0b0d604f03d010652af08ee2fe3342b6a
font_02_sfnt_off00010737.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10737 10496 bytes
SHA-256: d10f17a312cbcde5949be3da9c5191234d80188775346579ae88189b5e17a3d8