Malicious PDF — malware analysis report

Static analysis result for SHA-256 135531b9136011d9…

MALICIOUS

PDF

84.8 KB Created: 2021-09-05 16:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4908734720d79fe214e16bcf82a805c7 SHA-1: 7064fe55e6b15208d8dc0f2ba658a7bcfe7db7f8 SHA-256: 135531b9136011d9b3b1652a76b132eed996a38cc616960d8584adb28d290045
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or malware distribution attempt. It contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated, but the presence of external links and the overall heuristic firings strongly suggest it is used to lure victims to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://alarmy-kamery24.pl/userfiles/file/4875276497.pdf In PDF document text
    • http://agro-pasz.pl/ckfinder/userfiles/files/zewidobena.pdfIn PDF document text
    • https://jambukuning.com/contents//files/basarazepatojiv.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/46454038147.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/e469417893da10535fc6c64da66d8da0/63021236361.pdfIn PDF document text
    • http://pensacolahigh1964.com/clients/1/1d/1d652d7f5bd5fd2f3712913460b20393/File/33970626850.pdfIn PDF document text
    • http://caopump.com/admin/userfiles/file/vovojonebuvipotigovoxere.pdfIn PDF document text
    • http://dzbnf.com/upload/file///78635194482.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608aaf314f970---nometuzevulabotuze.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/a33c9e8f8bc1578f90f6023391028dda/vukinuso.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773e156fe91---guzogasalosuzeberolafoziz.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/65138f120ad6e09dcbe245212195aa1c/45542136315.pdfIn PDF document text
    • http://bioident.pl/photos_fck/file/febufubudadixariwaxavukos.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/77681421236.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1609684d82c8b9---todaroxulonufesipegek.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/f394206026fef057df0d0c672df310a9/wanujigo.pdfIn PDF document text
    • https://yenhuy.vn/upload/files/pujivokegizujogilok.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/vixewamemavuvo.pdfIn PDF document text
    • https://btsmstlucia.com/atomicsteps/upload/userfiles/file/7611378223.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/kapoturubev.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1607e349ee0162---satulazowarajufoziwatufo.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/zipaxolekesomeputepoj.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/d59efc0efca66e89f60491748aac4768/80795639549.pdfIn PDF document text
    • https://ratco-hardware.com/Ups/files/11859015007.pdfIn PDF document text
    • http://ithaca1960.com/clients/8/87/874e400c25abfb160fd1c0cf9913fcd0/File/20031203172.pdfIn PDF document text
    • http://studio5r.com/userfiles/files/53651105990.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ff79779f9ce---16763729395.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=hipaa+patient+rights+pdfPDF 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_off0000e61a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE61A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2C 18184 bytes
SHA-256: 823b92d83709cd5a65f6365beb68fd3afec7ae89845cacfa8df7c83c8d1cae29
font_02_sfnt_off00012d0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D0A 10600 bytes
SHA-256: 77f38ccda109bdb55d3e872a040a4a72d511fdd8aa00b6704aa52d83f0670e00