Malicious PDF — malware analysis report

Static analysis result for SHA-256 8afefbd99bd16de6…

MALICIOUS

PDF

69.6 KB Created: 2021-09-05 23:17:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b2b3ac46a83235f8182c99b7eeb7f727 SHA-1: 90ad0c0693cd38365c42f1a10610561a74a0b6fd SHA-256: 8afefbd99bd16de65751a9fb6dbf1af9731630ff1d307eb91dd13bc9cbdbfc33
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to other PDF files hosted on various domains, some of which are identified as compromised CMS uploads. This behavior is indicative of a link farm, potentially used for SEO poisoning or to distribute further malicious content. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://zjqzzx.com/uploadfile/file/2021090400102473499.pdf In PDF document text
    • https://agronlogistics.com/userfiles/files/23897010114.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/b47e64b565768f7a6f82ff4e2e397c2c/6479118546.pdfIn PDF document text
    • https://eqonetech.com/upload/userfiles/files/lisufumupadofogujula.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210815012059.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086ec44350f7---59665229235.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/bozutosewobudoluwisila.pdfIn PDF document text
    • http://xn--4k0b43gkwo4gn.com/upload/editor/file/lovepali.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/5840500306.pdfIn PDF document text
    • http://raisemoneyonline.org/clients/6/69/691275cf9a36cab982b2498ebdc715be/File/9702169233.pdfIn PDF document text
    • http://hesexpo.com/img/editor/image/file/66883795152.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/23225899335.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/9212922710.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/64666666896.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/476ac5f59851c58267a309c1585e937f/lisulekupanavoja.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/407056fc771f5b9b8e53c6f1609a97a3/rafugosanijigegobedej.pdfIn PDF document text
    • http://xn--90aoa5aj.xn--p1ai/ckfinder/userfiles/files/47644772951.pdfIn PDF document text
    • http://simpelms.nl/userfiles//files/tutejosepe.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ab26a3a9f8065c1d508594e9ab8e2614/83173416235.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/vozamoju.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/20865524425.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/vamarojunarajurozigo.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d085cf30f97---29767561401.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=durga+saptashati+pdf+in+bengaliPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/sezazisuvatata.pdfIn PDF document text
    • 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_off0000b0e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0E4 15880 bytes
SHA-256: 3bee915017dc4ebbeb2870cb4c00f02b4871c3669b543c09ea4502590204bd8d
font_01_sfnt_off0000d861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD861 10900 bytes
SHA-256: 389beb20242f3c923aa38ba7a03e2e7fcdddc1345a6603d6ee365160a4a76523
font_02_sfnt_off0000f11b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF11B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1