Malicious PDF — malware analysis report

Static analysis result for SHA-256 dda4f9728f0fe646…

MALICIOUS

PDF

87.5 KB Created: 2021-07-13 23:31:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c350e2efe22ebc2bb3348dab6e791e69 SHA-1: 1d7b401200403bf442cddb31f36c977fdea5667c SHA-256: dda4f9728f0fe646c6d7a9b8ab5e8f0b293b2232c307733f5dc9e5c715fdb39d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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=dodge+ram+1500+questions+and+answers
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d56d4d6722e---jubulifajefijik.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098c2e2ae131---xupafegexebunogogelekutuw.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160703e68d2fbf---zamavikejojod.pdf
    • http://anhuifan.com/upload_fck/file/2021-7-6/20210706164236395220.pdf
    • http://nwatchonline.org/userfiles/file/25672312923.pdf
    • http://tizianaiberti.it/userfiles/files/mewiwuxap.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/d0a7fbf62e5ae7b36c184dfc2515c7ed/mekoxora.pdf
    • http://abpaluso.com/upload/file/nulodanipaziburogavozi.pdf
    • https://china-glass-mosaic.com/userfiles/files/20210616_225639.pdf
    • http://www.toptehnik.si/images/6081940894.pdf
    • https://clearpatth.com/userfiles/file/fewinagazuwarigeboza.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/2af7dc0439be5685c1eab06b468e42d6/tarefovinurumosal.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c912470f94---tudukurobejosoranunile.pdf
    • http://snypes.nl/img/customer//files/bexovekowuxejarese.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8ba407126---11108345432.pdf
    • http://angelescare.com/userfiles/file/nuritagosudiwumujib.pdf
    • http://cambridgekapurthala.com/damana/userfiles/file/mirep.pdf
    • http://lideparts.com/userfiles/file/1622506257.pdf
    • http://anhuizhkj.com/upload_fck/file/2021-5-23/20210523201232607042.pdf
    • http://x-site.by/upload/editor/files/tusijakokunatozolotogafo.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b89fff3a429---16208214037.pdf
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/fivapopuwotilorufixe.pdf
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609603d2a1bfa---19970761044.pdf
    • https://advik.net/userfiles/file/vexovudemidutaxexapozal.pdf
    • 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_off0000f1dc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DC 16792 bytes
font_01_sfnt_off000109f3.bin
25be07b842b956d7689398e3247caa82f273fad04b219a652dd9c2999e80a8c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x109F3 11188 bytes
font_02_sfnt_off000123b8.bin
88a45fd2f8a48594585fb8c223c95f4db73fe0eeffd5c3781331caf15a3ce7c9
pdf-font-stream PDF embedded font (sfnt) at offset 0x123B8 17168 bytes