Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c8668e568ceeef9…

MALICIOUS

PDF

72.3 KB Created: 2021-09-26 09:52:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 89a4be79ec446b498bd4d2a120e848d0 SHA-1: 1635ccae5e6109974354c71599b1443542ec8534 SHA-256: 3c8668e568ceeef979b0f4eb16e2a01e6943f830ff58f0974bcd6c5e98ec97d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are structured as link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites or download further payloads. The file's structure and URL distribution align with phishing or malicious redirection tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://livbiopharma.com/userfiles/file/zovuvukitodalewegukugeses.pdf In PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133bfbbad72a---kixubetobudamisig.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/jirulajafedupubu.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/25905805286.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/87758933096.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a3187272aa---kedesoluwofafunuwemiredum.pdfIn PDF document text
    • https://karthikaspices.com/uploads/file/14573769726.pdfIn PDF document text
    • https://vilnius.cvzona.lt/resources/img/files/vuwek.pdfIn PDF document text
    • http://4rrecycle.com/files/file/wikikazi.pdfIn PDF document text
    • https://suruburi.net/mm/file/72512693796.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/8327361955.pdfIn PDF document text
    • http://terryloops.com/E/file/39351628071.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/jilubitinajo.pdfIn PDF document text
    • https://butchercurnow.com/img/shop/contents/fevekinanurum.pdfIn PDF document text
    • http://esistore.com/userfiles/file/7334951890.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/tamolafunolidokovalesek.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613dba00ea1c5---13947687344.pdfIn PDF document text
    • https://styliststudios.com/imagesTE/file/98882941277.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/kufudanux.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/venoxipewoduja.pdfIn PDF document text
    • http://biogenetec.tw/image/files/20210911_234858.pdfIn PDF document text
    • http://haphadoor.com/upload/files/famutanex.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630924668.pdfIn PDF document text
    • http://studiofranzoni.eu/userfiles/files/wonove.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=3+letter+words+with+i+in+the+middle+for+kindergartenPDF 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_off0000b45f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB45F 11052 bytes
SHA-256: 989e1be794a271189fc4143ebf07b7cbc725492c3358a1738878989a10cd61a2
font_01_sfnt_off0000cdc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e5d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5D6 17136 bytes
SHA-256: 3a6085e0ca21e857ded88d381640ef10457ee24006ac7dfa2b16bb6985b53132