Malicious PDF — malware analysis report

Static analysis result for SHA-256 90000ad97c2b809a…

MALICIOUS

PDF

87.9 KB Created: 2021-09-11 02:38:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b49824fc13b1eaaf72763e733f8caeff SHA-1: 03be3367599412de277e7aa3c3f3c9b76ff8434a SHA-256: 90000ad97c2b809a40aff30128cf87fbb2adaf8238df23ba4d3a1b0f30f80e95
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 compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/digixuvoxosemonabif.pdf In PDF document text
    • https://reviewz.eu/app/webroot/files/userfiles/files/wofudizizizilak.pdfIn PDF document text
    • https://dhesient.com/media/nodotimopilubetesowi.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/dapesedobetizisafomezagak.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/37851146915.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/pibufudusoxame.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613847df68b1f---jigovis.pdfIn PDF document text
    • http://njxinbell.com/upload/files/67692622582.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a2de1fe9c---feziditurotofare.pdfIn PDF document text
    • https://goldmenu.com/userfiles/file/motuvivodop.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/11847508873.pdfIn PDF document text
    • http://sheilahancock.net/blogfck/file/77671863950.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/ljr15pl7igf8nuqve7tbr5tnlb/98676651290.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/gowogegifuzam.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/11003747566.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/84773663279.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210911_240DAEA2EF7F9D4E.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/95903370699.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/78978749427.pdfIn PDF document text
    • http://seoaudytor.pl/userfiles/file/56798957437.pdfIn PDF document text
    • http://veterina-naslunci.cz/userfiles/file/gaduwemobumubatodowa.pdfIn PDF document text
    • https://promaxsuspension.com/csmimage/file/39203879675.pdfIn PDF document text
    • http://fujiya-burbank.com/uploads/files/40581458631.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/basutajufizamoguzep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=free+fire+game+without+filePDF 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_off0000f280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF280 17988 bytes
SHA-256: 08c122872ff6e7e840e1d20a1118f62fdb59d44176080c557fe0f1b1b12e767e
font_01_sfnt_off000121c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121C0 10552 bytes
SHA-256: 681746e8f783f0a388f8928cbeb4ba5ac0f5106dddba3397430f2353b44004cd
font_02_sfnt_off000139df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1