Malicious PDF — malware analysis report

Static analysis result for SHA-256 83518aca2fcb3fcf…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 08:06:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 26e4450931a6f8e9e05ed650c591e6c2 SHA-1: 7efc0c292381e0c65d1ff9fca48cc4c9b82c657c SHA-256: 83518aca2fcb3fcf0d91a02c22ec4b81c8b5c4cc1768877ab5c3e0a629ce70d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised WordPress uploads and other disposable hosting sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to lead users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8776572e5---99011254652.pdf In PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-4/20210904104920778564.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/dosugukaburazaponuseju.pdfIn PDF document text
    • http://gurukripapublicschool.com/userfiles/file/83941819092.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/92742879546.pdfIn PDF document text
    • http://artemon.nl/userfiles/file/pofegokafexigepewavekel.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/e118e4c872ad637f4b617f331b673d36/43956406692.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/48988748022.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/bisiboraniwizatowofowu.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/96391112865.pdfIn PDF document text
    • http://sabancilojistik.com/userfiles/file/66868487379.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ae3a1f729---41814998973.pdfIn PDF document text
    • http://patronusalapitvany.hu/public_html/upload/63467049849.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/38434861932.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d414f35d4a---kodusu.pdfIn PDF document text
    • https://kitapkapla.com/upload/ckfinder/files/baxepotexusegabop.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/85478839963.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/xegotuxodatejapubabexag.pdfIn PDF document text
    • http://moscreen.in/cmsfiles/file/69722344191.pdfIn PDF document text
    • https://kenhquangcao.vn/uploads/files/jijijokavufetifuwijaxiso.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/futigutivugerenajoxetul.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/gifojifepejuxirusotiworiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=remote+shutdown+androidPDF 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_off0000d4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eccb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCB 10700 bytes
SHA-256: e3810fce1256595a39172f1226517fcc5a934c621694bd94966f00069c276765
font_02_sfnt_off0001053c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1053C 17832 bytes
SHA-256: ce611ae09ab3c758f73eb0c41e3da30bb6a31eb3eb754745edc77694cc00f30e