Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c3975e4f712738c…

MALICIOUS

PDF

86.0 KB Created: 2021-08-29 20:09:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b72af119cdf98524e0da7ff2a848833d SHA-1: 405393dcada2f8694d208e7af364f388d565f338 SHA-256: 0c3975e4f712738cdf1a2f93660ca3cdcf0f8c24bf5740b5d4181a2b9a4f8ae6
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal the PDF acts as a link farm, pointing to numerous compromised CMS upload locations and disposable hosting sites. These links are likely used to distribute further malicious content or phish for user credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://sbnjl.com/userfiles/files/jolirajarafaninasenuvol.pdf In PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160d4a835b5d38---koropodoke.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/45ca3e406e47fd38c28d48df28040610/tisajosixifigebug.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/48453914685.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/7b41c58c699caf13615b919aa5cae579/situkefijalo.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16085cf5bcfe79---navavexanebuparemuwetig.pdfIn PDF document text
    • http://lookkorea.net/userfiles/file/83689281077.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/59dphcc5gtn2bduer6n5rgvavs/poluvolipogelatomulebizok.pdfIn PDF document text
    • http://syntrend.critical.tw/upload/files/zolasanebexewepupilugugi.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/83658715610.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/ridojolewesulibexiz.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/mujegagelubivizaw.pdfIn PDF document text
    • http://wongkungfu.ca/clients/f/f5/f5c316b966f29b3192b3e9e3c5714b3c/File/32064121470.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/e251a1978078301488036008dbd37877/21718402901.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15986e0b36---49395922431.pdfIn PDF document text
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/92c5723bb8624c29dd8170a0492cf180/fukivufezonawelujerotik.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/bh5qujvrj9d75le1m4rhg0sva0/16565943978.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/f2688osrei87r28pauro2mdjf5/wojewezunejironikudiru.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/00e1b5cadedab11160741e8911977ddd/xemux.pdfIn PDF document text
    • http://csc-020.com/userfiles/file/20210618202913_nfcgft.pdfIn PDF document text
    • http://chinalanpa.com/images/upload/File/zalifiguzobaxorepupudud.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/67973806140.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16072b4dd75d34---18433673526.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce52281fa9---xozuwamar.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fef2a90cde---57680745064.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fb5b445132---5098321077.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=how+to+add+text+to+pdf+windows+10PDF 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_off0000ea86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA86 10696 bytes
SHA-256: 3bffd1b1373cf2be16d818f74520b568ac20d64971f18c32b3fcc6b167250c6d
font_01_sfnt_off0001034a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B5C 18196 bytes
SHA-256: f8b5c96616bc4ad62412511994bdf7872bf95a52a6e3de15b3e0e1e83734436b