Malicious PDF — malware analysis report

Static analysis result for SHA-256 738e1ecdb16335bc…

MALICIOUS

PDF

90.2 KB Created: 2021-07-27 15:36:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c7705f893cb3ee4f2c971c6ada4e4b3b SHA-1: be554c8961674b55cbf6fee73024505e9f7d9d3c SHA-256: 738e1ecdb16335bc4c967e83fc83a264f10af63c0c63b68c0de9bb848eef3f16
164 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many hosted on compromised WordPress sites, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of a 'download' lure further supports this, aiming to trick users into downloading the embedded PDF which itself contains further malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/9kllvb0hlq7ehf7sr8uqttr5q1/jomuramobamuzi.pdf In PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/6c9069654489f3b4d10c62faed7764e1/tufiserosakuwelo.pdfIn PDF document text
    • http://954move.com/clients/4890/File/tetoponaloj.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/k9e5i79ja69jbi68bsa4n8j1s5/xagewubixudavebagowajem.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16071aeb645688---teretidofelusunobovam.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160706fd89f905---73250914659.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/699329ddc4af5e7812f18a99ec1cba7a/najilesevu.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/bb8dfaa6f1a7329cf6d9c5d565c40732/72098290188.pdfIn PDF document text
    • http://somogroup.vn/ckfinder/userfiles/files/71161696062.pdfIn PDF document text
    • http://mfahk.com/upload/files/kajugexate.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/dekeberuvarorofux.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/zozula.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/rifenosetuliramexow.pdfIn PDF document text
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/kunapelinujixarudaw.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/880d13e8a89e7e1b0a02084b173fe65b/6072205061.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/69341826062.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/34p3b9v59btkl9rnkbhs72pc29/31069420241.pdfIn PDF document text
    • http://laptopplus.be/app/webroot/files/userfiles/files/89784343301.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/jivuzorafurubewak.pdfIn PDF document text
    • http://eau-msu.ru/ckfinder/userfiles/files/tijifo.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/e823a6558e9e813b04eac205cd4ecd07/wokitem.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/1d133a36b1fba1b8acac0d11e4619857/19115018191.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/45456c17b1fbc2e15e3ec5b2941d2d23/64851775243.pdfIn PDF document text
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/26429597222.pdfIn PDF document text
    • http://topcudental.com/img/userfiles/files/15456192845.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=wifi+brute+force+attack+apk+downloadPDF 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_off0000fd9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD9C 16888 bytes
SHA-256: 28b6b2e2ad8eb7a0e94f44b00986304e58cdea3c84e8cf32c7c5135c14c0d040
font_01_sfnt_off00012985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12985 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001419c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1419C 10856 bytes
SHA-256: e8d7ae551db7fd82670802e5a3562e969209ed1674f5dcc6ec581b4b156e75d9