Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc9c91388f786784…

MALICIOUS

PDF

110.9 KB Created: 2021-06-26 04:55:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: ed433457062d6b771f240948e3b58958 SHA-1: cb80ab048f52d72bd9b68fd43549d93ef4bb47f3 SHA-256: fc9c91388f7867849e41a5d81a1616ffac1688dbbbb5c1d6ec81df564f9fcba9
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing the 'super-forms' or 'formcraft' plugins. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing or a trojan. The primary function appears to be acting as a link farm, directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/a0829b76a97d4e3e2fa9e6e13fefc5ca/pupolaveropadatu.pdf In PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1133e0d94---91796450645.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/32168751648.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/0mbb65r6ons0sh6emlng6n0781/25943276266.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/f310ef5af9001294379f37e58a91aa30/54088849625.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/37511913900.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/16073f7ca70fa6---jaxosarakejatovilatipor.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ab78a7bff6d---96985686010.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/wefebuvolevovexatadumipu.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/39709606047.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/5e17201261b83f538c785784af361902/jigofor.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/kunabisuxuzaluwepunedila.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5fceadb62---pabojokupilu.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b10cb707136---4381511850.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/a85g14l4b87m1sq3192lut1umq/13581393643.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/0f907172047f5d291895f7a6d3a5d83d/modaburafugam.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/1gfdpelng6v4fps4af6du8qfl3/54367756764.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160990fecc192a---51377956310.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=review+of+related+literature+and+conceptual+framework+examplePDF 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_off00014d5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D5F 17712 bytes
SHA-256: aa97f846d7b0901e2035d77e19e9f7030e2d43756599c2d8bba779f205db97cf
font_01_sfnt_off00017bf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17BF6 11104 bytes
SHA-256: 7945f08bd3817d5c4215d258e65f693ca62a3bd600e6decac8fe07d45724d07c
font_02_sfnt_off000195e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x195E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1