Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f83f13211f9d90e…

MALICIOUS

PDF

86.2 KB Created: 2021-07-14 00:02:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f4c6deb8ca7b57512bf69bd87b85b072 SHA-1: 1c67dab207a35109ab92a6e96f32cfbdc874aece SHA-256: 9f83f13211f9d90ea5000fce43f762d633c6a397f885213314800bfa1d2dcd43
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these external sites, which are used as a link farm, a common tactic for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607342e219937---fijowodupi.pdf
    • http://rockoncharters.net/home/rock/public_html/ckfinder/userfiles/files/kofesujatopalaveri.pdf
    • http://weifong.tw/fckimages/file/nebagepivazufutiw.pdf
    • http://kulturazebrak.cz/userfiles/25577366795.pdf
    • http://ankaser.com/userfiles/file/23056474650.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/8qlgcfb2cnr9eakv6ur92i06iq/zafitonidogagazulesodog.pdf
    • http://mhinflatable.com/upload/file/84429189943.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1a40bae92---nuzuv.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac7ade7ddf---gejasekulefunal.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160751670dca5d---54191241992.pdf
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/6edc47026ae55644cd887d769dbfb780/20961700583.pdf
    • http://agendatourvietnam.com/hinhanh/file/bajun.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b93c590cbad---1863544914.pdf
    • https://burgas-remonti.com/userfiles/file/memalibipalasana.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160782448a24a5---rufuxetop.pdf
    • https://xn--bankkrtya-41a.hu/js/ckfinder/userfiles/files/ragavatanureja.pdf
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/gidowizibevovuwawax.pdf
    • http://copelandreunionla.com/clients/6/66/66f6f3de7053633686652f51c4c00696/File/dikegutulivozupuvopexusu.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/i90lrot1h974diqtrjk3b90401/70258328256.pdf
    • http://natproperty.com/userfiles/files/dogiralamileseb.pdf
    • https://fa-vietnam.com/webroot/img/files/laxikuwenipufasuja.pdf
    • http://szwygs.com/upload/suvewezex.pdf
    • https://dalilak1.com/userfiles/file/vowogu.pdf
    • http://andrelandberg.com/userfiles/file/kibufatesunejed.pdf
    • http://poorclarescork.ie/images/52030268017.pdf
    • https://agrimal.pl/userfiles/file/22939898255.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085ccc60fcbe---tigopanoniguxuz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=metastatic+squamous+cell+carcinoma+meaning
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef14.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF14 16792 bytes
font_01_sfnt_off0001072b.bin
107e17965fe91c7f71b28130f602695339f6c7df8334be69b894ca864c2ee600
pdf-font-stream PDF embedded font (sfnt) at offset 0x1072B 10812 bytes
font_02_sfnt_off00011fcb.bin
cb54c135d89980ea62adcabb1d28da4b28410f87f1da0337e740b3484ffb9f52
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FCB 16644 bytes