Malicious PDF — malware analysis report

Static analysis result for SHA-256 b718fc8da41bb733…

MALICIOUS

PDF

77.9 KB Created: 2021-09-04 08:14:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4df8ecd0d6e1bdc3b2593ca02d7b40ba SHA-1: 2e31d32d129277ff798d99f595f2c62db6ea2295 SHA-256: b718fc8da41bb733d46dd86849b1c27c4ff487ff308a55f36f13a2d73ecc9ec4
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://testgit.begurholidays.com/uploads/userfiles/files/67906770612.pdf In PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/c98dnmg845d8nl23fpj1nq5q3g/65777418780.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/05/09/file/20210509_193819_188.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c9a5cda8f---xawiwagadupute.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/xikuna.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/t2koo7i8uciupm3nojtsm0pm23/vevasorebokabujuke.pdfIn PDF document text
    • http://lamexmarket.com/uploads/files/15851285245.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/e2cc1d061efd1b46bf1eb85a483b3b06/kekavazawefotokoru.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/uumhnn860c41lpnbpa1epuh3k4/zalalemefibuwometu.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/gipaxezogazaluduli.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/togumigogumatosa.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/56394283947.pdfIn PDF document text
    • http://olympusflights.com/files/files/xedanufudovuxefal.pdfIn PDF document text
    • https://derey.nl/app/webroot/files/userfiles/files/37760823242.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/rejoxovokaxa.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/riduzukisexevif.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/nekuxawasosul.pdfIn PDF document text
    • https://sinarwaja.com/account/files/86679634866.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/4rvnkr0t9tlntli9dnu2prpprs/56707503203.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa60c8b87cc---92107256312.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/39534aad723ce6de2cd302117024865d/dijibuzefizemamapuzew.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160892b3d0520e---kuloninabedapimukotak.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160c3a5e3e2ab2---banigomifawutog.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/bajoripumegupobuguposola.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=addition+and+subtraction+word+problems+worksheets+grade+5PDF 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_off0000c967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC967 17436 bytes
SHA-256: baf2825f58509ba0a2bd24af31a0c61d0454b607866eb790e830a501fc5e3d9f
font_01_sfnt_off0000f659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF659 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E70 11492 bytes
SHA-256: bf6a9cf35b431f2b03aa1c4084e25a69ae451d3188af27db75e682bf67d46bae