Malicious PDF — malware analysis report

Static analysis result for SHA-256 f2237a4cf7ffba32…

MALICIOUS

PDF

82.4 KB Created: 2021-09-06 09:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fd4854d52212a1d99137bb2cf4cd6081 SHA-1: f4f07adc1e37050755db61733ca5673b835d31bd SHA-256: f2237a4cf7ffba320dbac6b6c264b4af5c7b536eefa7b7c0d7a3fe3aff487399
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. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' reinforces this, indicating the PDF's primary function is to host and distribute links to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://archism.ru/uplcv?utm_term=desperte+seu+poder+pdf PDF link annotation
    • http://aep-tc.com/cache/fck_files/file/megikodewipavejos.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/84671961882.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/dixogegejaxixivujusuf.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/sobapagizitaj.pdfIn PDF document text
    • https://lapakunited.com/contents/files/pipinitilanebipafolulenip.pdfIn PDF document text
    • http://ryouhurt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zudilevom.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/29104143051.pdfIn PDF document text
    • https://dm288.com/slicice/file/xuvazito.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d0a69b463d1---sonazusesosiramexa.pdfIn PDF document text
    • https://synodradomski.pl/userfiles/file/62730824681.pdfIn PDF document text
    • http://slp70.com/clients/873855/File/83935274309.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/76965679785.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/53951303666.pdfIn PDF document text
    • https://lordoptika.hu/files/files/kumonejiganejamel.pdfIn PDF document text
    • https://apteka-wratislavia.pl/halatecza/userfiles/file/sijegusapujujawikabewapo.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/42370084372.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f52fbe3010---pinelosuxajud.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/4f8122c69ef37bb599702f95d8924a3d/mixikesibirazajiv.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/86401054123.pdfIn PDF document text
    • https://luminex.pl/upload/file/40530708907.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210824083253_o8ia6g.pdfIn PDF document text
    • http://fvv-hohenfelde.de/sites/default/files/files/webumeguwolag.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/80900151631.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608683398c6cc---davuze.pdfIn PDF document text
    • 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_off0000dbb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB6 19556 bytes
SHA-256: 35873c4ce74531c7f101b166db6efe781566ff8bb6cfe51e66883955243c8f21
font_01_sfnt_off00010ccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CCD 10188 bytes
SHA-256: 6fe830c3f233d149a4c575ff8cfa6868797d7b98b6ff852ef89106f8b2c6cdac
font_02_sfnt_off000123cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1