Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7b5883fa229bac…

MALICIOUS

PDF

75.8 KB Created: 2021-09-07 23:25:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3cbf793350057e1fa76499ebc81c9d10 SHA-1: 4bf1bb1eb72d6c286d43c09daafb0b9ab71be748 SHA-256: 8f7b5883fa229baceefbaf4ec7de096f607e651185c73454c04272f032774905
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://citytrafik.nu/images/file/rinesupid.pdf In PDF document text
    • http://pataibicaj.hu/userfiles/file/dubigubufo.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202108260522452345.pdfIn PDF document text
    • https://aaaxxion.info/images/file/29178417385.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/61586424204.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/opc6qdn7hk894c5se3ts7n5p4o/bititolatojujifavuma.pdfIn PDF document text
    • http://yarpb.ru/pic/userfile/98984093557.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/42738984957.pdfIn PDF document text
    • http://edwardlankin.com/clients/86087/File/35755292394.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a290f1adc2---64016787725.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/17dd2fd2cdea4c7ccf713c50d64a57b3/vitaganofaxumowo.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160aca5d0629e0---zevugusebatovebitixabalis.pdfIn PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/tepufumopozevufib.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/vn2i3b6a8edl02qghj1k6m646e/fetunalulemedoja.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/9d5im4ibd9pjede202p4hfcgt5/zepefofibegup.pdfIn PDF document text
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/pixalotaradizanivalo.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/dasedivilapujapaxus.pdfIn PDF document text
    • http://jakpaisanestate.com/images/upload/files/tasenipolulakubomevezot.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78fd996e92---28547663938.pdfIn PDF document text
    • http://md-servicios.com/userfiles/file/27024998268.pdfIn PDF document text
    • http://avistravel.ro/userfiles/file/41809542256.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/tofubekafi.pdfIn PDF document text
    • http://keacg.com/upload/files/lufelofulazukatufojer.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/6ec56f1addfa05c3e49e583ff5006348/larob.pdfIn PDF document text
    • http://relatives-united.com/clients/75139/File/87791412250.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16113641c96ae5---11710395312.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=english+file+pre+intermediate+pdf+descargarPDF 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_off0000c369.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC369 17252 bytes
SHA-256: cda2c0893fb4c05a766d5309d7ba0a8ca827de987d66593928fc9d1407ee02d9
font_01_sfnt_off0000f045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF045 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001085c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1085C 10932 bytes
SHA-256: 97e833b291e3bb63d91d781fdeeafc10d6eeaf2de1d0474718a7c07f13cfd354