Malicious PDF — malware analysis report

Static analysis result for SHA-256 a586ffcf56ba9ed1…

MALICIOUS

PDF

83.4 KB Created: 2021-09-19 08:50:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 83b26b51dbd098f538500b5cda64f047 SHA-1: d5c193fce94093c28fe8345f74e38d521efbe833 SHA-256: a586ffcf56ba9ed1638497e5e2b94ddeba0d0b58f4255240ded5261bafce1c35
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/8001d586ecfe725961e283afa6a8aeb9/38381867523.pdf In PDF document text
    • http://rainhouse.kr/data/editor/file/2698610316130773364bb3.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/51860699345.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/93685055274.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/28106237872.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/kolirewen.pdfIn PDF document text
    • https://edinburghpools.com/contents/files/4719259063.pdfIn PDF document text
    • http://poorclarescork.ie/images/davebibodubefazevi.pdfIn PDF document text
    • https://bcbc3399.com/upload/files/pudufiguki.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/161304fcfeba0c---wikeb.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/fufigufoxajavagawo.pdfIn PDF document text
    • http://ingegneriarossi.it/userfiles/files/ruvetafunevebefesej.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/zifux.pdfIn PDF document text
    • https://mygrind.ie/userfiles/file/92905044220.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/ribebofemopugopevumug.pdfIn PDF document text
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/xakatizawulerinuka.pdfIn PDF document text
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/19761531122.pdfIn PDF document text
    • http://pactolous.hu/upload/file/36405720778.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/ccb5e3a951a699d604347cb38e1ca3a9/bafiwuzo.pdfIn PDF document text
    • http://banghetretunhien.com/media/ftp/file/4154134272.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/23513560550.pdfIn PDF document text
    • http://bftt.marketsearching.com/upload/files/koxetozupigojuxeturik.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/54854000319.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=which+is+the+best+live+wallpaper+for+androidPDF 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_off0000e25e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE25E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA75 11004 bytes
SHA-256: b6c0881bdd89f5c26b27566b2c1402b5d7f0f7707fe44c4d6c989d37f70ea491
font_02_sfnt_off000113cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CB 17124 bytes
SHA-256: 759494eeb5a88a6961c8f7256c7060782920016e8dd3dac247c1f051f1e0e703