Malicious PDF — malware analysis report

Static analysis result for SHA-256 337641d7a2215926…

MALICIOUS

PDF

72.8 KB Created: 2021-09-15 19:03:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dfd72da2fb2a6e583ef8c7c04b9765b0 SHA-1: cc055f081af8a9097f584429b288ec69523d5cbb SHA-256: 337641d7a221592644b92f273b2df610dc97e22be451e3351c9102c538ea1a5b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the presence of external URIs and links to compromised CMS uploads and disposable hosting. The PDF document itself contains obfuscated content, but the overall structure and URL findings suggest it is designed to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://coretry.ru/uplcv?utm_term=rare+candy+gameshark+code+fire+red
    • http://internationalnetworksolutions.net/files/
    • https://intersensor.ro/v2011/Files/fck_upload/file/juzeribo.pdf
    • http://aj-freight.com/ckfinder/userfiles/files/1325623859.pdf
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/56de557f00412e19b29c38a85efbb862/wivoto.pdf
    • http://gamecoast.by/uploads/files/499749334.pdf
    • https://detskeihriska.eu/ckfinder/userfiles/files/xaparikabirodadufikomedo.pdf
    • http://rurisnet.org/images/file/jeperezokekenurab.pdf
    • http://tuecpa.com/file_media/file_image/file/nesagov.pdf
    • https://thebillionbottom.com/business_school/uploads/file/zilagapojexixi.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c5516124be---16622640702.pdf
    • http://happyhanool.com/ckupload/files/42042093896.pdf
    • http://www.octopus-quatuorvocal.com/ckfinder/userfiles/files/90615917064.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/161359eb3e94aa---38519262129.pdf
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/50d7a04cc51022349af6dbf968c1d33d/85871383324.pdf
    • https://smartech.lv/sites/smartech/uploads/documents/files/51099095885.pdf
    • http://bhk-aindling.com/userfiles/files/kuvoxozowudo.pdf
    • https://nichecnk.leaddeehub.com/userfiles/files/66236649423.pdf
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/84968567399.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f14ee0a58---nerepur.pdf
    • http://fatename.com/uploads/files/202109151521098439.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613019fd22d03---90215702773.pdf
    • http://twfbs.com/ckfinder/userfiles/files/64187832896.pdf
    • http://breakevenpoint.pl/uploads/editor/file/vimofugunidutaxer.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b8d5.bin
ea46ae2492fe7349b6b8b4534f79bc61510537bfd3315628ed79f4a912d35e23
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8D5 16388 bytes
font_01_sfnt_off0000e2e3.bin
a2463708aa09f60d3a228cbc34c32bfc5d6ba69237cd059879f74781cb2a10b4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E3 11032 bytes
font_02_sfnt_off0000fc2d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2D 16792 bytes