Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9ddb13ab1ab7870…

MALICIOUS

PDF

86.1 KB Created: 2021-06-29 06:08:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: ab09c7402b2e126bcc09b20f34810c64 SHA-1: 96fcce5cd26297494f8eb06a1b3f76ffe106852a SHA-256: a9ddb13ab1ab78704c021b3a1d614d282ac1915386ac0794ea97ac7720a7a5cf
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links pointing to compromised WordPress sites, suggesting it functions as a link farm designed to redirect users to malicious or phishing content. The presence of these links and the compromised hosting infrastructure are key indicators of its attack pattern.

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 https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a25dd3ed2c8---85356523610.pdf In PDF document text
    • http://advicetao.eu/pictures/file/juxuz.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/7610ac80b2e755e7eb2166e61f74ce80/fetedexogo.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/17580801827.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5238b7d68---62608827372.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5c1386057---11463216072.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/jikeaptevpckmrej6isfbgjg0g/71605877493.pdfIn PDF document text
    • http://moto-bike.pl/userfiles/file/93064901733.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/65713878624.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/34023579293.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/dupivan.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/6a29c64310cc89c474f93319258e9e52/xugewizasolev.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb467d63f4---90563113286.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b4783e935ed---pujagajam.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/ab3231ce71b2b835f2e007062f6a94a7/robelenamiligamumegu.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/v7jhts1mkeaika6k0lkujuocp4/86530457569.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b162475f7cc---bomefez.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/faadd5ea3b10237f10e6d37027bd7a10/jubapufunizedif.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b19e4267ee8---xomufifetakases.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/boxagawetukij.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210628_7F2D246C0B499283.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc50b3708f---pepuvufuxoforaxedola.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/60732335250.pdfIn PDF document text
    • http://unseretochter.com/images/file/51828959028.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/levib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=before+putting+on+a+hand+splintPDF 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_off0000ebdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDB 17592 bytes
SHA-256: 8d08f39a8c7ed092ff19ddd04e64e24608274f56691fd1af877aa61df2d1463a
font_01_sfnt_off000119d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131EC 10932 bytes
SHA-256: f58875d2f7a12e085fdb49b261228c780d284f238158e39e2808351dda7e94ee