Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8abff4795ce318…

MALICIOUS

PDF

93.4 KB Created: 2021-09-13 17:23:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a288210615da7e7efa8c7e86185a4480 SHA-1: e408c940e6b6dc6ca4b32185c5967f6d33f9ffdf SHA-256: 8f8abff4795ce31844b948886d34eb47ccc7037e95c426e2388b8d00fac88783
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to lure users to malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple external URIs and a link farm heuristic points towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://cityface.cz/res/file/mirukexevotazisoge.pdf In PDF document text
    • https://nguyenthelong.net/userfiles/files/24449846973.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e622296286---xamoridewajogatavasixune.pdfIn PDF document text
    • http://herve-coiffure.ci/files/fofifakujugopikowiw.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/65421002071.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338d75a86ae---zililewegekidif.pdfIn PDF document text
    • http://snft.ro/media/file/jixexepamavixarakitojos.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/wubute.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/kunezodi.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/salasakafivop.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/79539838386.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/32810135257.pdfIn PDF document text
    • http://okgwa.net/50/files1/file/fakudurekataj.pdfIn PDF document text
    • http://infosierra.es/images/editor/tabapuwulefetu.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/wisalonogufazagutep.pdfIn PDF document text
    • http://scpt.it/userfiles/files/53912505305.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/powafogoluxagazuv.pdfIn PDF document text
    • http://grandfiltr.com/files/file/jowiriteduwojez.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/kamaxumidiga.pdfIn PDF document text
    • http://marchmont.ru/imgs/file/46714681383.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/19282757083.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/7e3d3a0787b6169837eddef3a259b00e/82554052161.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/22021843477.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=tambola+android+appPDF 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_off00010367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10367 20324 bytes
SHA-256: e138af6f924b8e813c4666000911a158587a2fc89224ac713a7a528636b41fe1
font_01_sfnt_off0001380f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1380F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015026.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15026 10256 bytes
SHA-256: 2e4ecd81f63a2383e0e52502143412713f2b603c8e9adca477ac999e15685cbc