Malicious PDF — malware analysis report

Static analysis result for SHA-256 78efcfc8c5b70dc0…

MALICIOUS

PDF

83.4 KB Created: 2021-09-14 09:51:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 039aeac3a628ac837615d3ef5382a7ae SHA-1: e29474b6e9d7d96f9425c3667c43549f28406273 SHA-256: 78efcfc8c5b70dc0d5d5b1a8bce31afe88d8141a1aaafbdd842dc467219865ab
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The presence of external URIs and link farm heuristics strongly indicates a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://kondicionery-domodedovo.ru/upload_picture/file/12260905194.pdf In PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/kuwaxonorumabafina.pdfIn PDF document text
    • https://svenjakretschmer.com/ckfinder/userfiles/files/nawopubev.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/93229275005.pdfIn PDF document text
    • http://xn--krmer-dnnebacke-1kb72b.de/files/file/97572273379.pdfIn PDF document text
    • http://sun-green.eu/ckfinder/userfiles/files/78515363362.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/jutawimerugaja.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/3954445579.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136eb068c59a---todamosavivisirukena.pdfIn PDF document text
    • http://kaies.net/upfiles/2109051900280051821xw840.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/46793721972.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d605d32b1---58984659966.pdfIn PDF document text
    • http://tercovci.cz/files/file/kixegizivosovenibaxixufap.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/13091486338.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/nofaf.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210910192432.pdfIn PDF document text
    • http://emeat.ru/var/files/3069581299.pdfIn PDF document text
    • http://majedalkarkhi.com/pics/file/26258666842.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134edef36db4---litojazefozomusamesekimu.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d51c83b81---xukadomabe.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/f4fc024qkor099jipri29pkohq/suzivizelosuwulamov.pdfIn PDF document text
    • http://ketoanaca.com/uploads/image/files/60126532247.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pigotikujetafusedemi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=clinically+oriented+anatomy+8th+edition+pdfPDF 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_off0000e24c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE24C 16900 bytes
SHA-256: 0d7b6ff39916358cf90012f15ee1ea6aa48b6957889c3ffe896a0aa3dfd3d4a1
font_01_sfnt_off00010e08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E08 11068 bytes
SHA-256: ba9567d5e4c14a86370ace1aff3c99f976766b4cdc5c499a79b35951c88baa7f
font_02_sfnt_off000127aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1