Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ddc00ac6c66390a…

MALICIOUS

PDF

92.8 KB Created: 2021-09-02 21:23:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 467276cbf053c4101166e0729fb691de SHA-1: 26b7325bdd52e1ce362cfafe49dc47942404e8cc SHA-256: 4ddc00ac6c66390a38d81231b6e50aae02b14416eff72158c9ac9f5710d28f4c
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to potentially compromised or disposable hosting sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL patterns suggest an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://mini-garden.ru/userfiles/file/43668904037.pdf In PDF document text
    • http://nessium.net/userfiles/file/sosalita.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/wasamofokudene.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/d2ccea8c8ea1581370da12066c4f9adc/87326662380.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f21f779cb6---8150476018.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/35831288386.pdfIn PDF document text
    • http://amandamaitland.com/images/file/2578582130.pdfIn PDF document text
    • https://dietacud.eu/upload/file/tipoguxowizefuxogu.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/au0o3d6nhkhk5abpsrvuqk74c0/xuwidifofatup.pdfIn PDF document text
    • http://chapelguild.com/images/usr/55672191499.pdfIn PDF document text
    • https://anfauglir.com/images/file/45671886222.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/51929523698.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/39832594243.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/7925118bd1be0054815ac8aa5a8ef770/pozilawo.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/suxenojeribojibivosa.pdfIn PDF document text
    • https://giaynangchieucao.com/userfiles/file/vaduretiminigef.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/vuridonifunateb.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c897ba6cea0---debemoponog.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/78623461398.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a132cb2e0bb---43675200229.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/56984453148.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/87l0tp7uiakd9q8lm9l1go9di7/tutikatugerodur.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210704031435.pdfIn PDF document text
    • http://xedaptheduc.net/app/webroot/uploads/files/30888214214.pdfIn PDF document text
    • http://quetthe.com/upload/files/93078987090.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=resight+500+pdfPDF 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_off000102e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E4 19416 bytes
SHA-256: c0471506c8261f75993af6dab9b559cfa09c5637fbc61fbea56dcfaf4d0af23a
font_01_sfnt_off000135a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014dbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DBF 10548 bytes
SHA-256: 8e73e9604325f1ac3e49fbca6d0a97a9e94b4f00cfb370e03c833e59f5b21408