Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dd9dc567d0323e8…

MALICIOUS

PDF

72.3 KB Created: 2021-09-03 09:02:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 301a6810bb46a4ea97f8056b37539825 SHA-1: 1ee9dfd2658ad03c0a5ab1bd6f114f00afb5de24 SHA-256: 4dd9dc567d0323e83fa01cfc43f4a37860e994ddd32264c43344a14ce820020f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious redirection tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://infrive.ru/uplcv?utm_term=libro+de+gravity+falls+diario+3+pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606da5f36b9ec---48981543664.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160c3cd6d89bea---vagufibomubavivuwap.pdf
    • https://kit-veron.my/ckfinder/userfiles/files/78577863509.pdf
    • http://perfect-gallery.com/userfiles/file/72990418667.pdf
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/tejewodenopuf.pdf
    • http://51www.org/uploadfile/file/adb6e944f185664a88efb7fbaded0128.pdf
    • http://antifftech.com/uploadfile/file///2021050819350968.pdf
    • https://rajatotogroup2.com/contents//files/25158878802.pdf
    • http://chayka-svg.ru/files/24268456084.pdf
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/74981578143.pdf
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8a3a49cee---bupusazivof.pdf
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/35f308cd6a5b81765caff637c9f83939/pevewunow.pdf
    • https://cremyco.com/app/webroot/docs/file/logewis.pdf
    • http://vladjurnalist.ru/archive/file/wulov.pdf
    • http://annamsaigonlaw.com/upload/files/rodulevokubegeto.pdf
    • http://wsm.hk/images/uploadfiles/file/votetisano.pdf
    • https://nistd.in/userfiles/file/13309159314.pdf
    • https://lufty.cz/UserFiles/files/50738581052.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b368dc66e7---kidemebuvated.pdf
    • http://asokmontridental.com/userfiles/file/64063623576.pdf
    • http://3mfa.com/images/editor/files/58052586054.pdf
    • https://bamfieldrental.com/userfiles/file/wuradenebirutipor.pdf
    • http://hanhthien.net/uploads/file/toxajuxewulenagumupobeved.pdf
    • http://automsystem.com/UploadFile/file/20210623031221388.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b65c.bin
893f46541f19a72b952334bca35d0758fc742956fd7dcb096ebe582a631239f5
pdf-font-stream PDF embedded font (sfnt) at offset 0xB65C 16004 bytes
font_01_sfnt_off0000dfda.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDA 16792 bytes
font_02_sfnt_off0000f7f1.bin
f67792b2f057c6d42ed93585aa2019e53422b7dc0d117e949ac523f058cde61e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F1 11016 bytes