Malicious PDF — malware analysis report

Static analysis result for SHA-256 31354dccb4d6143a…

MALICIOUS

PDF

92.8 KB Created: 2021-07-05 00:02:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9eae976fc798aeb0c765000c710ab13e SHA-1: 7eb4bd9edaf7dcdf63ba1c0115a1c86a18bac331 SHA-256: 31354dccb4d6143af541914dc3c157153865d4a9de2a5481d3d334f4136bb6c8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://cructi.ru/uplcv?utm_term=chin+ups+for+beginners
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/8e64ca2cf18e1d617e1d37006cea2665/fegevanifazabo.pdf
    • https://bbpartner.cz/userfiles/file/80122627310.pdf
    • https://lemanssrl.it/file/75003414692.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090bf59d71e0---40710087149.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/dbf5997e583e9061e307ca0c7aad6597/gijiselegulex.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9f6ebea27---40888680811.pdf
    • http://architettodrabeni.it/userfiles/files/wokajozim.pdf
    • http://americansemitruckparts.com/d/files/melaxubirileme.pdf
    • https://btcauction.vn/hinhanh/file/nomemofagowuwozopelimiga.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c35f53ca0a---79354254489.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/834237e192ebd3e16894cce990f8712c/36705733523.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607d02e145fa5---buzetijugimatevigumo.pdf
    • https://bookatowncar.com/userfiles/file/movosi.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/e158c62e591325cfadcbf9fd90564a97/zokejabos.pdf
    • http://learningkey.org/userfiles/laxerikovum.pdf
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b55af52bfbf---16535904538.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608d50a79d85d---60760576726.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a94392c5f18---jigewiwesoru.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7f5e4f4c9---1183878281.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/ghbqvo74ccjdu1qimukg0lo640/vavivijogonizurebasuwubex.pdf
    • https://aneri12.eu/res/file/38811964804.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072fce752d29---92253278797.pdf
    • http://bereanbaptistashton.com/clients/1/1c/1ca8668e480cca1e897b6add33210fc6/File/58136488845.pdf
    • http://holidayservicemarsala.it/userfiles/files/gefaboduzavog.pdf
    • http://mawaevents.com/uploads/file/toxupe.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c67d72ccef9---telinemipagukamogejaro.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_off00010259.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10259 16792 bytes
font_01_sfnt_off00011a6b.bin
3dda191934a73089c404be2db312e43f4daca8ecf3a906a697ea4b7496f40e88
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A6B 19372 bytes
font_02_sfnt_off00014c4b.bin
95a35347af55144144f15a5daa0ddbbcaea81c6646e37b3eb0013d5a56d74621
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C4B 10600 bytes