Malicious PDF — malware analysis report

Static analysis result for SHA-256 441090f42eaf0d81…

MALICIOUS

PDF

103.0 KB Created: 2021-09-05 10:08:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7ef7146332f678ac11e7feef5e5c5a42 SHA-1: 72a99320476adc485205ff5cbac50699c255aa1f SHA-256: 441090f42eaf0d81bdf84ff2bea78de15b29d2f30517a23530f0e486c2a93e10
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to distribute malware or phish users. The presence of a download button heuristic further supports a malicious intent to trick the user into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/62ec898988a8ba4c5d98aaf362a53823/vamujopukelibawifofuginig.pdf In PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16115cae756f11---96968575720.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/7864ac57bc2682f0e9f093e0e1c2b847/74080944863.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/rekagojazaxoji.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/670dabb8349987914e2d96c15ce00d0a/wivusa.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/3q1338mb80aehejmmn4d92tagf/gokopaget.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/tipowijexojilakebobutew.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/xumazixusebidovubexo.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/kunegibarosafaxifezifer.pdfIn PDF document text
    • http://rfinshaat.az/userfiles/file/tipisigeku.pdfIn PDF document text
    • http://edallyshop.com/upload/files/xobategumikujizuned.pdfIn PDF document text
    • https://grupo-kayros.com/userfiles/file/xukorezamebedazonenuzerak.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161258f829b787---lajefesasiluzumofulezi.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16085e3d3c43df---40152075315.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/lamofuwetimamusere.pdfIn PDF document text
    • http://tramtronbetong.com/uploads/userfiles/file/gasenudezuv.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/78362699625.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/bebikim.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/81059239093.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160935c202ae6e---gibolun.pdfIn PDF document text
    • http://minerva-collection.net/files/files/gejepasodabaligifex.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/58paqa9ff4643iefahg4svnn50/41289160409.pdfIn PDF document text
    • http://isystem.hu/ckfinder/userfiles/files/56042408080.pdfIn PDF document text
    • http://bociany.sk/media/file/bopaparuwimugota.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/768920aaffa55416aa8d5f6f5c744ecb/83724501072.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/28845709280.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=pendirian+perseroan+terbatas+pdfPDF 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_off00012d25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001453c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1453C 10584 bytes
SHA-256: db3d4c9731f41429e9d98c02f831c4a51fede859a2f03f16cf9febf590943994
font_02_sfnt_off00015d46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D46 18828 bytes
SHA-256: 20ff92f16d1e854f023618ffd74136ca12c46bea6bc56036bd2d482d4ee69bae