Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e23837a6399fc56…

MALICIOUS

PDF

73.6 KB Created: 2021-09-19 06:16:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c9b0bd1398c1d6c2bbae40c1698a5dc5 SHA-1: 89614e202c03c0df72d1e5850d36443219314d9b SHA-256: 6e23837a6399fc564df45450ae53cd9f26fd1ae06a96043a124b6b18efa49e52
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 disposable hosting or compromised CMS upload directories, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pistant.ru/uplcv?utm_term=1911+blueprints+pdf PDF link annotation
    • http://www.focitabor.hu/userfiles/file/dowimajafusimeloz.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/80510710787.pdfIn PDF document text
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/69236438988.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161305a0bd99b3---varamolev.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/90950504752.pdfIn PDF document text
    • http://lube-stc.com/ckfinder/userfiles/files/fuviwuto.pdfIn PDF document text
    • https://coopinproject.eu/ckfinder/userfiles/files/kevudofenapuxofozejunudo.pdfIn PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/55021403561.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/17891747054.pdfIn PDF document text
    • http://baihsad.com/userfiles/files/20210902_082958.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/6907826242.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4a1391c52---milagobekenu.pdfIn PDF document text
    • http://winso.tw/userfiles/file/49659176939.pdfIn PDF document text
    • https://k31szmq42-nu28.com/contents/files/32528137323.pdfIn PDF document text
    • http://willettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/2796441405.pdfIn PDF document text
    • http://sperrincaravans.com/images/file/46596492.pdfIn PDF document text
    • http://saveursetsavoirs.fr/image/file/lenufo.pdfIn PDF document text
    • http://homeopathyhk.com/files/fosubotigofiloguw.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/5289318047.pdfIn PDF document text
    • http://khachsandomino.com/hinhanh_fckeditor/file/dufek.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130197d94da7---bitadujugo.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/1s9n72gl5qtk1a3sh43oqqh0cs/61494103984.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d746263c2c---kokamed.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/7336902398.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_off0000bd2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD541 17016 bytes
SHA-256: 60e77cc3b0e9b6d29b3d798548936b106311e23689306e105a24f2773d57ab80
font_02_sfnt_off0001017e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017E 10572 bytes
SHA-256: 3648c86201c4ea6f32fd297a80be41bac92552e214acb1948fee620213980c95