Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7c13cfb30df7f40…

MALICIOUS

PDF

84.2 KB Created: 2021-09-23 09:07:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1686e2bc096cd5b16ddf46fa1f030a5c SHA-1: dcf977b2a9b30eb401e1f8c9b68d8dd98e1f9b25 SHA-256: a7c13cfb30df7f40883569764e89b8b4d4a5631c915fc6b8a5ef861d3fba5796
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous compromised websites, many of which host further PDF files. This suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, and the structure is consistent with a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://locnuocvietmy.com/Images_upload/files/78049791362.pdf In PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/c9dc171477f7a71b5c39b5b631b4f280/40989414958.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109200021514816.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/fosetuxulojigibo.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/95765547233.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-22/20210922231519659453.pdfIn PDF document text
    • https://quote-supermarket.com/userfiles/file/91595038885.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff66834561---mowakenepebipapibe.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/27870277723.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/9268575169.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/34009294198.pdfIn PDF document text
    • https://alexspa.pl/userfiles/file/3351460595.pdfIn PDF document text
    • http://capriololaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wixevusedogabin.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/2nqveohs69hhgunf7174pcfre2/36139122812.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff937cf26c---21670831.pdfIn PDF document text
    • http://grupophi.es/uploads/files/3778993027.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/273m65iml2huefa7t8pa5cqspl/72231821079.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/guxitodafagezabikidirazu.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/dejemisixoji.pdfIn PDF document text
    • http://vaynhe.com/upload/files/gofokawiru.pdfIn PDF document text
    • http://alkanboya.com/files/file///kisawefuturomal.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3970e6d18---sokuwiwixa.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/66421737834.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=usuario+root+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_off0000e5c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fddc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDC 10172 bytes
SHA-256: f595a0cfd5d5f6ecef17cf342c222f37015e5b0cac08ff4586f777c5c2fb7b95
font_02_sfnt_off000114b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B3 18008 bytes
SHA-256: ce2aa6b973351ddd0fe2831e539c68bb92e0c0666e4f8ea16c4ce56a5e45db5c