Malicious PDF — malware analysis report

Static analysis result for SHA-256 d550a11fd9cfdf9f…

MALICIOUS

PDF

84.6 KB Created: 2021-09-08 15:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 73fc365a470852b6b542567bfd698772 SHA-1: 33aef6ee143e222abceb63533678552789ad710c SHA-256: d550a11fd9cfdf9f953944c8830c123bb9b76314c2cd206a92b10893940ea02a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports the attack pattern.

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://chcial.ru/uplcv?utm_term=increasing+and+decreasing+patterns+grade+3+worksheets PDF link annotation
    • https://nasco-ye.com/uploads/file/midiworaki.pdfIn PDF document text
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/jogenewuruv.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/tawetenofefuf.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/73338065702.pdfIn PDF document text
    • http://kaus21.com/userData/board/file/fedon.pdfIn PDF document text
    • http://duplisite.com/userfiles/file/60839759440.pdfIn PDF document text
    • http://benedictinoselrosal.org/ckfinder/userfiles/files/resajimuwafegigodewivim.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/fivosurigijuv.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/vawaxi.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16133e641b3192---42466505470.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/muzazojudefodezefugopin.pdfIn PDF document text
    • http://cpils.com/userfiles/file/98227258860.pdfIn PDF document text
    • http://misr-consult.com/userfiles/file/dadokidukobunapexej.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135377d4124d---xowetepibajam.pdfIn PDF document text
    • http://wefocusdesign.com/upload/files/puturividage.pdfIn PDF document text
    • http://kleinschadenexpert.de/userfiles/file/83572842594.pdfIn PDF document text
    • https://firsatpin.com/calisma2/files/uploads/57358712712.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/gisuzerubepajotimodoraro.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/sejuloxiwowegulaxapata.pdfIn PDF document text
    • http://vivo-mebel.ru/upload/file/13742262844.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630594641.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/73282082934.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/97c6d3776d5777527c6dd63f0c274db9/pakamozu.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_off0000e1ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1ED 11048 bytes
SHA-256: a4cc627542a18447fa2f86da2f48aa44c750408b9d218c1a1bc0e87ab3644f7e
font_01_sfnt_off0000fb77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB77 18940 bytes
SHA-256: d4b724e73bcbc04780d398c25e54f4908c8681f1ec1bae73e0f30d983d3717de
font_02_sfnt_off00012ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1