Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf58de56048182b8…

MALICIOUS

PDF

66.6 KB Created: 2021-06-09 05:17:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 560366686c2c73f2f03da84eac1c9afa SHA-1: 740a228ad8e1fe5d087b561da2c9d8f310012677 SHA-256: bf58de56048182b81d0f184902686d2fac5afefafb76cc39da21a92c3f9cc307
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to academic materials, likely to trick users into clicking the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smidgel.ru/uplcv?utm_term=elementary+principles+of+chemical+processes+4th+solution+pdf PDF link annotation
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076788234a92---vojeligo.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210603_FF8BACF40D180743.pdfIn PDF document text
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/vtu8ld75310spvvsc52a0juinc/97407864951.pdfIn PDF document text
    • http://blevy.com/ckfinder/userfiles/files/6340017381.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5c8fa738c---7503284876.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/fgp031fks750jouihgg5qtigd6/kesujaxosanekugez.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/62054248593.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/29453127035.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bebb06ab12e---jidilox.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/f737d8588b289084817376c8f4bd3194/28535424070.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/jb6ecbbm1e03ku06n11r7i2g77/nosifu.pdfIn PDF document text
    • https://orldoc.ch/wp-content/plugins/super-forms/uploads/php/files/gtbbct2nepgp71cbrbkklpe376/12739559432.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/fc5e6d6f7a70b4bb95b0a2e65b2b83dc/vajaxoduxisipuxi.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/rutaguxokukovijo.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/8a93743788a46ed4ae7a381a04a23bc3/78762410397.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16080d5eaa40d9---54301824102.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6DF 5544 bytes
SHA-256: bba13fa5fd8482927a4d10f865543ebbd156b1a83b62d91403f566fbbfa6231a
font_01_sfnt_off0000d998.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD998 10380 bytes
SHA-256: 58572c85ed9c5999a55e5d4ec4c4c5eec1f618e0ad2581f9d3dec07377afe67f