Malicious PDF — malware analysis report

Static analysis result for SHA-256 679a3b2aa9da6d6a…

MALICIOUS

PDF

70.1 KB Created: 2021-09-26 14:56:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6e03b7147a59456c90c68061be854919 SHA-1: 2aeef9fd9114b590648b7fb8bd34f2549dee295d SHA-256: 679a3b2aa9da6d6ae104341b970e0a8ae2de9844e3051f77cedfbf709b318b83
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure. It contains minimal text and a single image, suggesting it relies on a clickable action to redirect the user. The numerous embedded URLs, many pointing to compromised CMS uploads and disposable hosting, indicate a link farm designed to obscure the ultimate destination, likely a malicious site or download server.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 2 text block(s), carries a click-outward action, and is only 70 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://sibaco.ru/ckfinder/userfiles/files/widoximevem.pdf In PDF document text
    • http://gld-lining.com/user_img/files/suzanem.pdfIn PDF document text
    • https://www.opsclown.it/ckfinder/userfiles/files/19210267680.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/20455829562.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/56579354934.pdfIn PDF document text
    • http://metallpress.ru/files/10699019334.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613558f0b367c---82939172146.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4bc4ff77e487344f26a1e24eef0df74f/25496112022.pdfIn PDF document text
    • http://forepic.com/_UploadFile/Images/file/22582636923.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161487af7c6936---27235419017.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/1208902248613a03538e55c.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/senuzowagura.pdfIn PDF document text
    • http://xn--80aa5alfu.kz/file/runutaf.pdfIn PDF document text
    • http://qbcar.ru/ckfinder/userfiles/files/kavidiwogonibatozoxipus.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f79b20c28---95078676834.pdfIn PDF document text
    • http://baoveantam.info/upload/files/roxogazovozetisos.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/kepakenu.pdfIn PDF document text
    • https://rendszergazda-cegeknek.hu/ckfinder/userfiles/files/69231428736.pdfIn PDF document text
    • http://jinshi66.com/uploadfiles/files/nonafozosaxaw.pdfIn PDF document text
    • http://a-pro-peau.fr/userfiles/file/9934653085.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/70334486311.pdfIn PDF document text
    • https://marlin-shop.ru/ckfinder/userfiles/files/52984888979.pdfIn PDF document text
    • http://lifebeachvilla.com/uploads/image/files/45284698675.pdfIn PDF document text
    • https://natanashoes.com/kingkong/userfiles/files/88401442423.pdfIn PDF document text
    • https://pro-biomed.com/admin/userfiles/file/27426304091.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/fug6rbb3p120lrrejc0f1bhf3d/75769413857.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=victor+hugo+notre+dame+de+paris+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_off0000b4ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4EC 14528 bytes
SHA-256: b233603f7591ee18edcc0fa6a5009005016751eb842c4ebfe169eda2cfb3a783
font_01_sfnt_off0000d8b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B4 11088 bytes
SHA-256: 085d8e6745b903b38cbe3290e962d1b29d95146061d9a68f714fe268f99426c7
font_02_sfnt_off0000f239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF239 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1