Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d532e0ff9b5da4…

MALICIOUS

PDF

81.2 KB Created: 2021-07-07 01:10:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 9e7614a525195a6d8001707139ca6cd1 SHA-1: d0bb90eb0f719af3af26ea5e931e1ddab1b54d86 SHA-256: 73d532e0ff9b5da4995c2f2ac767986ce3d450484a75404d5ba4221b0c771afb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and disposable hosting. The embedded URLs suggest an attempt to lure users to external sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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=logic+in+computer+science+modelling+and+reasoning+about+systems+pdf PDF link annotation
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a981cf93817---1700574891.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/dumipimewusovuwa.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608835d3e44fd---daxufezuwowokividuwew.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/47268f4b0a407980f7a68e0e047e6088/94909972545.pdfIn PDF document text
    • http://mazurubezpieczenia.pl/zdjecia/fck/file/38476824435.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/mefonaguvatazara.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/66000092641.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/64432455407.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609a80823a697---8223924569.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/27732401012.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d98594667b---10339097537.pdfIn PDF document text
    • https://castel.ro/userfiles/file/jubofonoxezegijofe.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3e000895c---65282732544.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16074253d96961---setetemejupowovalise.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/0888b31afdc3d82443b784ca45c2db4a/29671850850.pdfIn PDF document text
    • https://noddy.nu/images/file/fikofopibajo.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c482557619f---95846319524.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/469421785.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f7150ad2a---bitele.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/038923bc98c2c285560317f5a031c33a/36480653349.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/40929c5111d6f049331570ddd399c88d/47042834235.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/6o8ste8qmtqfbc8o1qbcmqgi4d/ludotimoniruretov.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/vvsltpgjh6k9n9pso9t28usp9b/sujokexunubifu.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1609781c453dad---13751928601.pdfIn PDF document text
    • 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_off0000d7ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000effc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFC 17424 bytes
SHA-256: 391b48d64085819447652da644571e394eb6365d1cf60bd0a2b8cb203d53ff33
font_02_sfnt_off00011cb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB8 11272 bytes
SHA-256: 06bb34c328efb9798e4cc7df4944f0f9e8b529583f1621cef71246fd64076dbc