Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6c850e4cd99f5bc…

MALICIOUS

PDF

88.1 KB Created: 2021-06-28 21:46:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: fcd8f4de08754796207f054200d9ac5a SHA-1: 6f287dc547a8736e09525a8b74e64cfc28c786f2 SHA-256: d6c850e4cd99f5bccbdde38998202f78eb9e9798c1f2ad713b98bf45ba3aace0
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file exhibits characteristics of a phishing or malware distribution lure, as indicated by multiple heuristics flagging it as a link farm pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV detection further support its malicious nature. The embedded URLs likely serve to redirect users to malicious sites, potentially for credential harvesting or second-stage malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://geodez.com/pliki/file/71835641711.pdf In PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070709919c81---97414790953.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940713b7844---45472373478.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/4401ac47de9b0a3c027273dfa306ca0a/15119683249.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/e05e17efcf639508c1315fd1e344d157/xukorobagofiwikexaj.pdfIn PDF document text
    • http://okulsanmalatya.com/imgup/file/5997139321.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/b266edc295bad88812a8a87a5f789080/sabanuxevu.pdfIn PDF document text
    • https://rhodium.vn/uploads/news_file/69664870844.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/615843a066462d392047052061483ea5/kinikidewabivaputexe.pdfIn PDF document text
    • http://visit-pune.com/userfiles/file/widejologubijab.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/741e70bfc83d8ae06ac5cfb7aba52bf9/5207188162.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/81af6fd04dff578bab812a87d0ecb46f/vajefemomofubudamuluxipi.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160702cbd1de90---6973984052.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2841b87f4---kulefuguvuxegerulufirow.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac09ff82e2a---23249223484.pdfIn PDF document text
    • https://thaihoanghung.com/upload/files/71693153718.pdfIn PDF document text
    • http://wasserburg.pl/userfiles/file/rafip.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/6pq14s6ngc72l7ggkl4rtqsoh4/juxaketosakagibijopisafap.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8bba4dba6---nelaxubip.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2e02ad38a---49367031791.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/sb49cnlupm9lqvd60lqs4clg25/joxerabolipexowulu.pdfIn PDF document text
    • https://dineflon.com//files/saxinekumiregifonu.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b082fcbadee---53857908350.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/8210971925.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/m29kn6elg70db1m1ogj0h0u8ha/61327783383.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/56554753140.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/82069586144.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+do+you+remove+blood+from+carpetPDF 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_off0000f111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF111 10912 bytes
SHA-256: 3b3da6741c561ea313c26c810923bd2e2d8d73f0b81aba4ab01e6d294d288168
font_01_sfnt_off00010a36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A36 18568 bytes
SHA-256: 39139737e906ebf769003251f9b9dc138857df762627ed454e9a3eac78908eaf
font_02_sfnt_off000138fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1