Malicious PDF — malware analysis report

Static analysis result for SHA-256 76f11e8b23e39b83…

MALICIOUS

PDF

74.4 KB Created: 2021-08-18 20:45:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a2d307525a441328dd6e0e9d3e18fd26 SHA-1: dd5bf8cc8de35f8a8627bb3e983836ca97727b22 SHA-256: 76f11e8b23e39b83d28f1b3a4ec7ff6e27dd64cab232a9f56d0b9ae5d59d8b37
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware through these links. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

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://perfecthospitals.org/ckfinder/userfiles/files/53965152371.pdf In PDF document text
    • https://vildmarksjagt.dk/userfiles/file/91146193988.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/e06a0f6d83618c16f1d118851f309844/jovibol.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/24864a60b211137397d7ca2d187922d6/xidanapugowopowegil.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160747c875d06d---xolorijiriwovuwoxokonax.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/kizokebokulub.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/5a6f4ff632d103cd114eab7e44bf5d03/97536974500.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e0a50dbbd---pufunopobop.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/72e88c6e1d5406ef74d192a4b1d051b5/80500209902.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607b08055b115---ruxezutaritel.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098fcdf1263c---82679463129.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/48100962399.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/konerutaxewunelapipidolif.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16110780b55fb4---46776549032.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202105200343.pdfIn PDF document text
    • http://fgsconsulta.com.br/ckfinder/uploads/userfiles/files/dizekasalodemo.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ca06f5a243f---41521022946.pdfIn PDF document text
    • https://agrimal.pl/userfiles/file/83926653589.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d818536e503---92595404462.pdfIn PDF document text
    • https://birudongker.com/contents//files/jeboxubuvutidaletoxo.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16250149916942.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610514b750dd4---puselig.pdfIn PDF document text
    • http://twothirdsmajority.us/clients/38522/File/278032927.pdfIn PDF document text
    • http://mobilephleb.com/clients/2/2d/2d2188d13063160162e6e2bbcdac547d/File/36318805833.pdfIn PDF document text
    • http://cuacuonductudong.com/upload/files/wukonalejetevebekuja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=relative+adverbs+worksheet+4th+gradePDF 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_off0000bf85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF85 10928 bytes
SHA-256: 64f033369e9e58371de68aa3a3185ab02b6210acd59cdcb969049909b8d39d86
font_01_sfnt_off0000d8d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D9 16588 bytes
SHA-256: 69c32c0658e8b394da304b16d711cbbc24ecbc0c07b701a798456a97845fb62c
font_02_sfnt_off0001036d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1036D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1