Malicious PDF — malware analysis report

Static analysis result for SHA-256 730f43e2c3aac6a0…

MALICIOUS

PDF

119.1 KB Created: 2021-09-17 23:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9cec8df6235e8b659f5d379c6ebbac39 SHA-1: b5b74cfe081f53e88c13693811b902b15ddc56d5 SHA-256: 730f43e2c3aac6a0da47f8c106c5d185b58aced062f58b3249a991b02360a802
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating it's likely a phishing or malware distribution lure. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS uploads. The PDF structure itself is minimal, suggesting its primary purpose is to host these links rather than display 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://aptwash.com/userData/ebizro_board/file/puzumaxaxemoruru.pdf In PDF document text
    • http://denkobarbell.com/_upload/files/sukamesu.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090415544724.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/woxomunodikikakidiruga.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/72325446070.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/bazezufedobijigejikuf.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/14371099659.pdfIn PDF document text
    • http://royalrep.com/userfiles/files/6588921983.pdfIn PDF document text
    • https://medbillings.us/lightspeedweb1/file/44991048627.pdfIn PDF document text
    • https://maisonforville.be/documents/file/76772565865.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/2b03eaaeb107a0401ddef71d35ce7168/jipul.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/452970c3a89856e80cc10385f32dddbf/81913884325.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/jodukafezunetegukug.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133de576aba2---5333477177.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/zewun.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/64402678086.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/1634504364.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/siretadisak.pdfIn PDF document text
    • http://usagimatur.com/files/others/66717733673.pdfIn PDF document text
    • http://ttccid.com/userfiles/file/lifudov.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/talope.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/34779923033.pdfIn PDF document text
    • http://irinaburmistrova.ru/files/karekodusunovezalijab.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/nazapuvolusanuxufizef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=smallest+computer+memory+unitPDF 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_off00016a3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A3E 10824 bytes
SHA-256: 65ac6c822497be3996af341a12771deb0781ab6b05bb367759c07dd300bc8b81
font_01_sfnt_off00018337.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18337 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00019b49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19B49 19680 bytes
SHA-256: 4cd2a8caccd309daa875055a2be3d08c5e1d5ab9345940b28f804f4447491dc3