Malicious PDF — malware analysis report

Static analysis result for SHA-256 57f937d17ea0da1f…

MALICIOUS

PDF

81.4 KB Created: 2021-10-10 18:47:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1e755ddfbd557488e33dc79109861a83 SHA-1: b8f7ac607cbe98b3666f00a1cab6e4c181db6ad4 SHA-256: 57f937d17ea0da1fdbb2379009edb7d4cf43a8dd8db7708e53e06778fa060541
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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 http://win-sonic.com/ck_imgs/files/xulitavivabimugifofumop.pdf In PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144442c8fe05---nuvawixenimejiwotona.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/37006720795.pdfIn PDF document text
    • http://vagtteam.dk/userfiles/Files/tifuzinijexesiwip.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/kazasezufakukuxubovedape.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/87288118770.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/jemubigowu.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/52857479686.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615cd7b0a40ea---66966827885.pdfIn PDF document text
    • http://handgun.ee/media/file/mifotobikiju.pdfIn PDF document text
    • https://joinvita.com/neu/userfiles/file/65084542422.pdfIn PDF document text
    • http://stavebnevyrobky.sk/www/upload/files/kezumu.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/goxibuwuru.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/xakokepido.pdfIn PDF document text
    • https://aynadakikemalizm.com/resimler/files/52841760331.pdfIn PDF document text
    • http://twgo8.com/uploads/base/files/202109160103341499.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/lewijufulukagobijisaz.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/puwifowitobosujipomuje.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143160d9823a---55699564416.pdfIn PDF document text
    • https://isosklo.cz/uploads/71120632630.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/74212436181.pdfIn PDF document text
    • https://calienglish.com/ckfinder/images_store/files/81202162449.pdfIn PDF document text
    • http://spad.kr/userData/ebizro_board/file/ramol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=svg+to+eps+converterPDF 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_off0000d813.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD813 18636 bytes
SHA-256: e64c47db3ab9d9c4fad175ccb7b7267e19348847b72b36a417d05b7f08fc906b
font_01_sfnt_off000108ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108AD 10388 bytes
SHA-256: 9754381944b33771ffdba10e3291274137ccfebcfa33f6bbe0127a8de3b5691a
font_02_sfnt_off00012056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12056 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1