Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3f28cd9ecd13b29…

MALICIOUS

PDF

78.6 KB Created: 2021-09-11 07:23:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fde893a15149e7ef08decc32055a92f0 SHA-1: 2867b54c6058b98f3da64049c290eccb0cc2b8a7 SHA-256: a3f28cd9ecd13b29dcefe70dcfae997dfa70599119eac3f3a22415fdd232970b
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous PDF links on disposable hosting further supports a malicious intent, likely to distribute malware or conduct phishing attacks.

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://adikkedua.com/contents/files/18178105770.pdf In PDF document text
    • http://www.hon-ro.hu/userfiles/files/21892282421.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/vefilatebiwe.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/91697471732.pdfIn PDF document text
    • https://nvsrolko.org/ckfinder/userfiles/files/62698452086.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/lolurudizen.pdfIn PDF document text
    • http://5thaveseniors.org/userfiles/file/runom.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613017c96f3ed---1701741045.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7229b2d76---39837225042.pdfIn PDF document text
    • http://www.thaitofu.com/image/upload/File/16839271673.pdfIn PDF document text
    • http://grupposcorcia.it/userfiles/files/38913526273.pdfIn PDF document text
    • http://netichikawaya.com/userfiles/file/64344697831.pdfIn PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/vesuwudogo.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134f1a2a336d---retarubotizudixosebezav.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd8b6b43fa---98293978809.pdfIn PDF document text
    • http://kotrackusa.com/fckedit_file/file///20210905_9_22_56.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/17784210352.pdfIn PDF document text
    • https://onlineadda.net/ckfinder/userfiles/files/kawadozivusetutowaxebo.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/gekujodawizasote.pdfIn PDF document text
    • https://nistd.in/userfiles/file/todirexasato.pdfIn PDF document text
    • http://designbeginnings.com/upload/file/nolevuditudoripate.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16132839c16c43---kanurunifusoduvetup.pdfIn PDF document text
    • http://niktid.ru/userfiles/file/54644684321.pdfIn PDF document text
    • http://www.drivingschool-brno.cz/files/files/88056147962.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=zombie+highway+2+removed+from+play+storePDF 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_off0000cbbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3CF 17752 bytes
SHA-256: 417142f227d4ed8366857b1f54f0bf4ffebdc01ffb1d13eed197e00000ddb500
font_02_sfnt_off00011229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11229 11332 bytes
SHA-256: 4c678c920822338656b985193160b51bda0822626540ba6488244adf0e6ab592