Malicious PDF — malware analysis report

Static analysis result for SHA-256 521317f817bbd2a0…

MALICIOUS

PDF

100.9 KB Created: 2021-07-02 19:43:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 9d446fdfd3e264875f16092ed57041fe SHA-1: e0785c67d4721e8150d34a708e080fa13909cb3e SHA-256: 521317f817bbd2a03dfb67f309c0838ec477b76ba279a9fd0a18d4ec67bb7a39
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised CMS upload storage locations and disposable hosting sites. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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://atmaircenter.com/lb/userfiles/files/pivetezofodezonip.pdf In PDF document text
    • http://esangsok.com/upfile/files/20587083607.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/9a85a904d75d86f72320895c2149dc49/dobejapifenibokexe.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/6rj7jcui5kqe8ejp5doapumvem/rigotaxoj.pdfIn PDF document text
    • https://soechi.net/userfiles/file/88359149990.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf5adbfefd---vonate.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c33cb99751c---tepove.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/kiviwapun.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b303a34c7b0---39388892325.pdfIn PDF document text
    • https://studiopros.com/userfiles/file/In PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c50d2e7e4f6---73211227626.pdfIn PDF document text
    • http://rotarycochinharbour.org/ci/userfiles/files/95280601917.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609421d3e23cb---45773095671.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc1215ee2c---nozalenusukoz.pdfIn PDF document text
    • http://eviljoy.com/UserFiles/File/pofijawenomabixebam.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/79922775392.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/82441579939.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/7rk84bc5gvj7b1k4eckua3d5g1/sezigimanadasixegovuw.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a2c765304---50562977363.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ttqcm9rct15a2a06sbbrbck0i6/57781417046.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d91920a2cf---10394185749.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/4f610e1644f1b402c1201220d0f7a7fd/fesibuxivodipanivo.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc8c0fad326---xotukaxukagirevixozalolox.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/69796117672.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160b0588455460---xamafoje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=behaviorism+social+learning+theoryPDF 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_off00012a8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001429d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1429D 16396 bytes
SHA-256: 8da022756b5943925039877a11ca4a883d726bf43402eba6c5202e3139073e88
font_02_sfnt_off00016d1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D1D 10912 bytes
SHA-256: c89a1b863553bdb7ddf0309cb45e9f560c2b1003f94aa868ab9f2d14dc580bf8