Malicious PDF — malware analysis report

Static analysis result for SHA-256 8832502f52ea0eaf…

MALICIOUS

PDF

84.8 KB Created: 2021-09-01 06:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fcbb3ecdb0272140e5b984fbd4199e92 SHA-1: 8fb3fba27f4d55fc8a2d18d45309d3f436a44333 SHA-256: 8832502f52ea0eaf20bb660d4e75947565b2a9512553bfd7e2cd8ba55c132caf
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on various domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://concilianavarra.com/userfiles/files/xetozabefuxijon.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa8f70fb32---xafuvuwanijuku.pdf
    • https://healthmatters.me/userfiles/file/29703335264.pdf
    • http://haus-st-otmar.ch/userfiles/files/zuzadisopujadelugav.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/2876a5ded664cd7c3abb1d7f72228970/gopelusakimamubipomodiko.pdf
    • http://foto-klub.dk/userfiles/file/31510476757.pdf
    • http://gndpta.eu/news_objects/files/xabikod.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d9fa31252a---jafikipogadakawifi.pdf
    • http://tcsm62.org/uploads/news/file/lonomajarilavu.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b83ec8817e8---8755089402.pdf
    • https://loctra.net/userfiles/file/27433707349.pdf
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/60382362311.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-1/20210501231204163297.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b3330daf4---49893670501.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a37edfc99c1---91806677213.pdf
    • http://se-ty.ru/uploads/userfiles/file/95394824228.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609727d92725d---jatujosikopabil.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/1mvv5a54lhrqequhc7qn1vh6g5/19497609110.pdf
    • http://kuppersbusch.hu/userfiles/files/zozebemetapelakubovipiseb.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608aacc2bb702---detapalinamulid.pdf
    • http://recit-de-vie.fr/userfiles/file/29017855959.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a66a8f8ba00---tasosoxudukuded.pdf
    • http://fedoro.ru/upload/file/69585661034.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=through+what+lenses+does+light+pass+in+a+compound+microscope
    • 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_off0000e224.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE224 16792 bytes
font_01_sfnt_off0000fa3b.bin
fb5352e9d25a556cce5f26b56db0e3ae40f938dc071ae7c47a0dbdad0e679e36
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA3B 11112 bytes
font_02_sfnt_off000113d4.bin
e9c0fb5e15851d930a1ec705a99b40427000929481054cfd9f95ce82cc5857c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x113D4 18828 bytes