Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7c9087608249cb9…

MALICIOUS

PDF

83.9 KB Created: 2021-09-20 19:00:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e13534d9a27b0fbdf676cfdadebe3044 SHA-1: 31ba2b5b36ab2eabca9e8247bfd8e77c97767862 SHA-256: f7c9087608249cb9887cbdd60fffd51e330895d9ffa302d5a6f5300e9e3b0b0b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

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://servmed.net/userfiles/file/35696624202.pdf In PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/95333916770.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/30719782110.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/niserudon.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/11457805448.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210912115311_ogznd4.pdfIn PDF document text
    • http://www.keizerco.nl/userFiles/file/66641592695.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/zelalezatomanan.pdfIn PDF document text
    • http://ubytovna-krumlov.cz/userfiles/file/sororuvaviruzu.pdfIn PDF document text
    • https://ms01bet.com/contents/files/kibemejavugufuwudipetula.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/mugurefekenamab.pdfIn PDF document text
    • http://billsky.ee/files/file/ruginibos.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/40816026536.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/cec3467bd7ed1f503683128ac3525208/23156266137.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318c7201611---pupipumug.pdfIn PDF document text
    • http://arcadia-fitness.es/userfiles/file/89406925041.pdfIn PDF document text
    • http://hflbdq.com/uploads/file/11020543801.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/banemugutexotepaw.pdfIn PDF document text
    • https://arerp.kr/data/file///39849718904.pdfIn PDF document text
    • https://airxps.com/userfiles/files/xupeduv.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/xodigu.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/sasavixur.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613dbed8abcca---98613699910.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=q+mobile+android+price+in+pakistanPDF 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_off0000df2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2B 18876 bytes
SHA-256: 19ad2bbdec228748124e25c4ce05bf7dbe96481080a7e16577c16196322577e2
font_01_sfnt_off000110b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128CA 10968 bytes
SHA-256: c7ccc9e6369e7c82de6f1d7e22651c0ff6f716c230d9715c96fc3db1cb79f869