Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6b98511ec43a8bf…

MALICIOUS

PDF

84.2 KB Created: 2021-09-05 03:23:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e871fb349533635cd0afb9e51065544e SHA-1: db8b777b67719e2511206cb48a588f9fe015424e SHA-256: b6b98511ec43a8bfff4404acc87c8002b3646619139332a4d02e67e5f1653161
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/da7kv4o3pap9g4iie46rph0ev4/54371536707.pdf In PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/73167759703.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/7027b8c5acdc76688b72870911943d17/buvepejilezikuwes.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/3aa4aba2d3598831aafc15c22b678e36/kutux.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941af9b2d36---riboriwet.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbcf9cb686---52265382142.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/resewatikuxi.pdfIn PDF document text
    • http://sammyuriasproperties.com/userfiles/files/dotan.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a63fa0ecd3d---tonitugufigonorawifujatix.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abca75e204---66551814447.pdfIn PDF document text
    • https://globalybm.com/ckfinder/userfiles/files/1628346580.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/9c0177ace10f809eebb874b64ae86c3b/31135292553.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/doripenupozizazarok.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105f1399dd62---4391083979.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/30728355832.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/93668359934.pdfIn PDF document text
    • http://debeight.net/UserFiles/File/64101334269.pdfIn PDF document text
    • http://sivam.pl/files/file/79783387237.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/c9d15c3da506e3943bdf28435967c628/zukotanizufuserelok.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/vereviruparuse.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/vefazelonosififipuramu.pdfIn PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/36540998657.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/52253156348.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/olin2tb6ufoca37m1rhs4662v6/sividizuxawig.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/83735615672.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/dajidukafuvezujowutowe.pdfIn PDF document text
    • http://kaies.net/upfiles/file/ritulazem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=swing+trading+stocks+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_off0000e410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE410 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC27 10868 bytes
SHA-256: 0da451809b3315d1789020c1f44ac34cb48d1e96838e7a2f3aec24df36118a95
font_02_sfnt_off0001153d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1153D 17532 bytes
SHA-256: 1a3dd1c324f61079589d01b1f08ed7e5404299497e42b3a64801353f1f8e2d02