Malicious PDF — malware analysis report

Static analysis result for SHA-256 5aa7981fc0313163…

MALICIOUS

PDF

88.0 KB Created: 2021-07-29 22:58:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2df4bb32fa68a315fd7187f6f5450109 SHA-1: f677d2b563075b22873f4ca1c3fda422e240dd88 SHA-256: 5aa7981fc031316392493f418df07cc66c79154d63bac9f28e72611cbfdc1e7d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS uploads, indicating a link farm designed to obscure the final destination. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this is a lure for phishing or malware delivery. The ML classifier and ClamAV detection further confirm its malicious nature, likely involving JavaScript execution within the PDF to facilitate the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/f484d664d659de5bbcb8c897f89ee5de/foxigamom.pdf In PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/85mltp68aen4mq96d2hsomkb13/30550570378.pdfIn PDF document text
    • http://lambanghieuquangcaogiare.net/vietkiendo/upload/file/36310734587.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/nepiduvufixaxibetojowerok.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/e38cfe064882ce389bcc76cec980b2f0/97204832640.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/zepilegened.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/6r52l6s859bg5ecs84mmrh4ft3/jolivalage.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/bf5828253ed6fe3217aa4f05790051da/57648508472.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/38ur047orrsq9ns9038n5h0v1f/gupelizavowor.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/jatudalovirovij.pdfIn PDF document text
    • http://twxcd.com/img-aim/files/fepunaro.pdfIn PDF document text
    • http://prime-standard.com/piceditor/file/julakizulodoje.pdfIn PDF document text
    • http://jwnorthclassof70reunion.com/clients/c/c6/c6167e942b76adab5863fbee8ae727a7/File/galugi.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/344688c4d65cbd2d955b1d9eacd218c4/41416327178.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/80707436035.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/771707d3423177e6fe49c3c54447ab74/nojusizazipivuf.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/82557351007.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/buxotadepemubarebux.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9a354f2ee---ramaguvixi.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160f17167b7804---94854133071.pdfIn PDF document text
    • http://xnkvinatimex.com/uploads/files/1161109920.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/sotaje.pdfIn PDF document text
    • http://kadernictvo-svetlana.sk/editor_uploads/system/files/28018775642.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d439b1876d2---giriba.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=que+es+una+metafora+y+ejemplos+para+ni%C3%B1osPDF 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_off0000effd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001080f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1080F 18060 bytes
SHA-256: 1f6c06634dfa0b003b2a06841d2c82de95af596d792e33e696d7d4dbde2e3266
font_02_sfnt_off000135ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135AC 11128 bytes
SHA-256: 9c9520b16031cefccb25c6489c20a403614c013d655d5641355aaee3552a026c