Malicious PDF — malware analysis report

Static analysis result for SHA-256 41cd1f75c2c90669…

MALICIOUS

PDF

83.7 KB Created: 2021-07-06 01:14:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 6b93399e8731f901450be4a0221f3e93 SHA-1: 39e64f8f9ecb81afa47e39c52b0f8e2c83fb46fa SHA-256: 41cd1f75c2c90669bf179be9244cd4b132157d1673f18701ef7c9441ea82b6bb
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a link farm pointing to compromised WordPress sites, which in turn host further PDF files. These links likely serve as a redirection mechanism to deliver a malicious payload or conduct phishing. No scripts were extracted, but the structure suggests exploitation of PDF vulnerabilities or social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://wastran.ru/uplcv?utm_term=overactive+saliva+in+mouth PDF link annotation
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/2d95676462b35fde7f46bb5d6a45ac63/20095297648.pdfIn PDF document text
    • http://ducthoaudio.com/upload/files/17730155005.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/7c0vbnicj3dp1rbffc3q12ijq3/wegovudexomiponinotuxu.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210516054542_dz5pcd.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbf0ee2c187---72086090398.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e5533ce9c6---49323458973.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606de63cb9e1a---52093225213.pdfIn PDF document text
    • https://parkettworld.com/upload/files/4882287465.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bde8d262aa7---towipepizudunaninuzoz.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607066e694379---sutezalowe.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9713e1401---vufakiruzuluzok.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae36c1a58d---tikijetuvezofigiguj.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/8d0b00e4c323d450baf4d57831f7c345/xixoxavur.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/obdkdj51qms6ot7hm31g30rugk/81913451245.pdfIn PDF document text
    • https://drvishweshwari.in/userfiles/file/woradaf.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160ab9980a6fc4---7248096873.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/989f5d203c3d7d19f781fceb9083b67d/xolalorisovowavujixopem.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/43133891787.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/882f2ba9762bd0527e927f2a04b32855/60324853546.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160a502810e82b---20790879478.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/fijivotetenesegukev.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/7bb62ab168dc01522cf39b7d3c4a07a8/jofeliti.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/8c9995f7126eaf6a451628e36217e64a/kowiwukiwe.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084b69855eb3---ramerewufewopasukodunuj.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160790ad23b5d2---bepafemudir.pdfIn PDF document text
    • 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_off0000e3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3C6 10684 bytes
SHA-256: b43d2c14a7f53bc8b115ba8fe85c0f3cc4dfcc5649fe5ff26192e8ad2fce0ff1
font_01_sfnt_off0000fc1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1D 17260 bytes
SHA-256: 8c82307c2b5c42e0a2ece1f3c62f7a7342d34f2c698c2f51084b6fb04d6b1809
font_02_sfnt_off0001295e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1295E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1