Malicious PDF — malware analysis report

Static analysis result for SHA-256 a36eb2806a02dfd9…

MALICIOUS

PDF

74.0 KB Created: 2021-08-12 11:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d045b65b7d1c80f6bbf4446a52646ef8 SHA-1: 323713c736776f45602ab2b4e1bd2c377e292924 SHA-256: a36eb2806a02dfd93f2438922139dba9592577591d3f0dd0aecbe8fe989f53a0
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF acts as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. The embedded URLs, despite some being marked as benign, contribute to the overall pattern of directing users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://maychamsocda.vn/images/userfiles/file/zaperol.pdf In PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845d61de544---vupinelagosurigulekitez.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/xolopirakegomuwidapevu.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/64ufiph6u209cqcj12gsi4i8cu/julumonosedaxonudul.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/bofaboxovisujowodowoli.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/66529987492.pdfIn PDF document text
    • https://sapporopools.com/contents//files/53424754447.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca7ad84158---77001457497.pdfIn PDF document text
    • http://abwrva.com/uploads/files/ravidemim.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d8b74e304---27759654514.pdfIn PDF document text
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/nowuxuxi.pdfIn PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/28375904682.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/17275063775.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/xapurolokasovol.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/24f3935345fdd1312e80647b843f058f/fasegig.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/p19ra05vv19h4k8fi4o9o12t28/1864133005.pdfIn PDF document text
    • http://cuanhomkinhtoanthang.com/media/file/52607144671.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0bfb28f2e---bafakisewapona.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7ca36c58d---fogaritire.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/87333672602.pdfIn PDF document text
    • http://lukasikgroup.pl/Image/files/48099555353.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a19ae85a64---jejafoduwosu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=10.+s%C4%B1n%C4%B1f+biyoloji+test+%C3%A7%C3%B6zPDF 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_off0000bc43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC43 17680 bytes
SHA-256: bffa04a05500c088665d03c8dcedc03d10b187d6d0bb0567fe9e07eb608be88c
font_01_sfnt_off0000e7e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E5 10992 bytes
SHA-256: 24238c7e2d89514afe26c0e419d6eadeb6fd2573d3b5c8a0fe9a70ee00801342
font_02_sfnt_off00010119.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10119 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1