Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cf1ff6093727698…

MALICIOUS

PDF

79.2 KB Created: 2021-09-17 10:07:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5397bfc9f68bb4fd957fc93ebaab5c53 SHA-1: 22faa592838f14a93427a2e491dba0243e8b560a SHA-256: 9cf1ff6093727698ddb16ae452ef8a72041da90342ce7b9226f7efd4fc0845d8
156 Risk Score

Malware Insights

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

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs and the PDF structure itself are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://apsencollege.org/test/fckeditor/file/87515499177.pdf In PDF document text
    • https://wildarium.com/ckfinder/userfiles/files/zebunof.pdfIn PDF document text
    • https://mimpiindah2.com/contents/files/zumamivelekijabifijazi.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/19005888045.pdfIn PDF document text
    • http://www.haztartasigepszakuzlet.hu/pics/file/1339683201.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/78289592935.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134b8c92c51b---84622102163.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/dedazekexelabonalipesokuf.pdfIn PDF document text
    • https://gopherscopes.com/userfiles/file/46368929331.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/napobora.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/43841943024.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/62337982441.pdfIn PDF document text
    • https://berettyotv.hu/userfiles/files/jobubitozalezividomatik.pdfIn PDF document text
    • https://widepolymers.com/userfiles/file/losusolarigakaw.pdfIn PDF document text
    • http://krukewittfarms.com/userfiles/file/38539716096.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/57943326669.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/subeveten.pdfIn PDF document text
    • http://stitesattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12584724481.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/mazixefizogurolimuxuxon.pdfIn PDF document text
    • https://saigonservices.vn/images/uploads/files/xulowijizemudemonogu.pdfIn PDF document text
    • http://kevinmcallisterlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/waziwutusa.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/3bbcb2fb561d27c6d005cd931bc38da8/62930566151.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/miziloj.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/7873e22524ed3df78fb53c907fa9c631/rageki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=show+contact+list+in+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_off0000d487.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD487 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC99 16688 bytes
SHA-256: cdc2462c022b6e0e074390a03fae5675b562f6da5ec8c12b9f9c3bae499c92a7
font_02_sfnt_off0001179b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1179B 10496 bytes
SHA-256: 64b9821fd72c5820a5329857eda4fc487cda4948bc8fe5f0338985920eab58b6