Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3dfe36111cce81d…

MALICIOUS

PDF

85.8 KB Created: 2021-07-06 18:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 17583c557ff793ffd2a0f8cc4c0307d7 SHA-1: 55512186ce8d1eb97cced7434178887f9adb865f SHA-256: d3dfe36111cce81d29f17a1677f0178b3396aa179b08de303a0d005563219bfa
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the presence of multiple links to potentially malicious content is the primary indicator of attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6931081610---vapoxovijilutan.pdf In PDF document text
    • http://ahlhy.com/uploads/file/060904421288.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8904847ee2---88155972476.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/29999927533.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c0fb7217f---fogonumobuwuvu.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160990418e6557---zazelarevisofije.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/96009670373.pdfIn PDF document text
    • http://gotween.com/userfiles/file///rodazalumewowalekapubavis.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec66645dd4---pakepe.pdfIn PDF document text
    • http://debden.org/userfiles/file/novugorisedoneperepaxa.pdfIn PDF document text
    • http://synerfreight.com/syner_upload/images/files/gobeluzujugotoralategewu.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a38bc74d750---defiji.pdfIn PDF document text
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/dogg0m9botvhgsco81hj9hi909/7985847241.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/5e2e51d68bf541e7151a7d6cbf7149b5/6174003045.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/dhth91f5aoigm9lvi9pl9uuvbl/dikatujegidajopiji.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/86235419812.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/7383247736.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/52658961929.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b44ad39531a---19482783045.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c57d5eacbf1---19831089810.pdfIn PDF document text
    • http://jump360.co/upload/files/20210623163415.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/213cb57ded25ae5c6f37061b136199eb/pekebagupiburewaz.pdfIn PDF document text
    • http://asfalon.com/__files/file/72362538502.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/3119008127.pdfIn PDF document text
    • http://ehsclassof64.com/clients/b/bf/bfa5c4411462ceee4a19e543862d902c/File/94254792334.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=what+does+little+miss+muffet+meanPDF 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_off0000ef07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10719 16416 bytes
SHA-256: 1bf665ec9c971ed4ed960eeae3765047034b7dfb86343c22ccfd35aba089a80d
font_02_sfnt_off000131bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131BB 10612 bytes
SHA-256: 85d988c1614878292e79c2d01a6a12d240810f5b4ec308ebef5eb94058959e61