Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4c921fb79de5c50…

MALICIOUS

PDF

73.9 KB Created: 2021-09-09 05:31:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5b5f15be43269137138f1ac1ada2da0e SHA-1: 2468e20e7e70cfccc657ee61a8680d0729f44c7a SHA-256: d4c921fb79de5c506d0ed8ee503a12c7ba9d969005344170dafe7380cf513a49
164 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://cplastik.eu/data/cms/file/16613616452.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/252fcbe2da63fc12b1521ec35b5ab7a5/taxiruro.pdf
    • http://jljemc.com/upload/files/kiwuwajufipasozexit.pdf
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/borurudowu.pdf
    • http://villabrown.it/userfiles/files/zufuwaxewopoluvelesimib.pdf
    • https://chataigne-cevennes.fr/imgs/files/nepuzemukurovelimobamojo.pdf
    • https://mamadona.ru/ckfinder/userfiles/files/voxolobaluvoxi.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a52cc5dc4---89899552274.pdf
    • https://agentcctv.com/userfiles/file/3339014497.pdf
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/tosuresokefuxag.pdf
    • https://nutstudio.it/userfiles/file/23056411145.pdf
    • https://educhina.mn/editor/files/91556241912.pdf
    • https://anitt.in/ckfinder/userfiles/files/90050910440.pdf
    • http://sarica.com.tr/ckfinder/userfiles/files/bevamimikopipugozakamuma.pdf
    • http://satisfytech.com/ck/upload/files/vasodadizarefibavuwaxi.pdf
    • https://malayalamfoundation.org/admin/my_files/file/8293848514.pdf
    • https://arendic.cl/files/likobodibuzu.pdf
    • https://tch.lu/files/files/42524348299.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1613870423cfe2---28832447122.pdf
    • https://viceda.com/userfiles/file/60770755309.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613258cdc9d54---kikutopinuberarute.pdf
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/pixodaboduwokumenarawur.pdf
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/totumuvobagifitomavama.pdf
    • http://anipetkingdom.com/webroot/img/files/nutibijiwerilebojozut.pdf
    • http://www.mecateengenharia.com.br/ckfinder/userfiles/files/62957524796.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=harry+potter+1+sinhala+full+movie+free+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b80d.bin
54f52c86db2202d860a1950808ea689928db8e850117a5de8a504e8e709cea6b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB80D 18016 bytes
font_01_sfnt_off0000e756.bin
f94350f66ee7e848fb99c5a78a086390f0db3fefdc20d026cdf471e7447926da
pdf-font-stream PDF embedded font (sfnt) at offset 0xE756 11172 bytes
font_02_sfnt_off00010153.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10153 16792 bytes