Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e6d550ae8a303d2…

MALICIOUS

PDF

85.7 KB Created: 2021-09-14 02:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9991e08acfee4180a8e46f648df484d0 SHA-1: 203f8ae1c203f515082a154d9d6855c680bce6a6 SHA-256: 9e6d550ae8a303d214fbf3f067e3a7e1283bb11447385c7c310f0eb29b1a1764
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 ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a link farm pointing to multiple domains, some of which are hosted on compromised CMS uploads and disposable domains, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161348cf4c264e---70468143698.pdf In PDF document text
    • http://ecohort.com/userfiles/files/7246340948.pdfIn PDF document text
    • https://ubitanduk.com/contents/files/80864307793.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161331f5533374---95233213799.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/8eb3d71760714b53ecdd3e0493fca527/83188010063.pdfIn PDF document text
    • http://suachuaspa.com/upload/images-content/files/likenuja.pdfIn PDF document text
    • https://www.campacinter.com/image/upload/File/72636921608.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/nazoxuvoro.pdfIn PDF document text
    • https://soudurelauziere.ca/upload/editor/file/fipowutapanumupomomisuzi.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/26572596682.pdfIn PDF document text
    • http://pagyesa.org/userfiles/file/20210907025452.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/vopefe.pdfIn PDF document text
    • http://wirheiraten.de/images/file/patejiburexuju.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/86863275342.pdfIn PDF document text
    • http://sweepinstyle.com/userfiles/file/78298007075.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/nubuluvawakumimaninera.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/zokebipisepumira.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/xudaburi.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/rugobuwadaruwenofukojej.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/ruxixegi.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/nelonunumiviv.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/79994039106.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/28262307259.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=app+name+androidPDF 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_off0000ed9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9E 17392 bytes
SHA-256: 0731f79eb03053b323c23756d37c0c8e583b832bc6266a02d11b582aac3c5ef7
font_01_sfnt_off00011a65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A65 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001327c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1327C 10224 bytes
SHA-256: 8640aefa9f6d1dd22d322d178ce6473b53c5d13d8cf82745911d11da26c0c014