Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f986b6d37cbe740…

MALICIOUS

PDF

80.8 KB Created: 2021-10-21 14:22:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 23b863ee15f40e2e8de535f7bf6533c1 SHA-1: 3560d41057837a0deb01aad08addad6f80270135 SHA-256: 9f986b6d37cbe7403321ddff3e3d6487ad9f90b863e03acd894ce136579560de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised CMS upload directories and disposable hosting. The document body is heavily obfuscated and appears to be auto-generated content, further supporting the link farm and phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1616dd6ee8f3ff---fomolusu.pdf In PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/75468895313.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1616d0b628c647---zivozetig.pdfIn PDF document text
    • http://gutachterbewertung.de/userfiles/file/mubipivefudatuxewolosox.pdfIn PDF document text
    • http://fabtur.ru/upload/files/zivuvirekagonapisati.pdfIn PDF document text
    • https://ismet.com.br/ckfinder/userfiles/files/vovoda.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/95770059818.pdfIn PDF document text
    • http://premiercontractinginc.com/files/file/mideviwunozoparivosoba.pdfIn PDF document text
    • http://jfhconsultancy.nl/userfiles/files/wofepuxepe.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/66800582647.pdfIn PDF document text
    • http://iwayman.com/uploadfiles/file/211016063316972020ap9jff.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/49143508367.pdfIn PDF document text
    • http://warmistore.com/userfiles/file/49515031260.pdfIn PDF document text
    • https://textolinguisticsolutions.com/upload/editor/file/zurujobawopug.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147de4191e69---potovotajuramakufe.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/19141085751.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/guralu.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/29687120163.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109161201184885.pdfIn PDF document text
    • http://bhk-aindling.de/userfiles/files/gekufajipebakeriwed.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/10222750150.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/5879abccdd0fd166be6faacba248cf9e/11765432010.pdfIn PDF document text
    • http://medicalproduct.hu/images/files/12604956032.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/cmwvf4RlXg4/uplcv?utm_term=is+it+if+i+were+or+if+i+wasPDF 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_off0000d9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B5 10096 bytes
SHA-256: 6f148844d9fe69b620898af65c4d8d99005402c0035410fd20bdc9bdd72bcb1f
font_01_sfnt_off0000f075.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF075 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10887 17316 bytes
SHA-256: e05ff40176e2901403a8d5ad21c6516bd5842183ea939f14e666c89bfb19cc79