Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5323982a453c09d…

MALICIOUS

PDF

97.8 KB Created: 2021-08-20 00:17:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ae0cab0785e33b134f90a9569a87ff6e SHA-1: 6f839ba9e23afc180167e67adb40a564118d761d SHA-256: d5323982a453c09d567962beeece0ef8e9f87955c8264eb8bbee9ef6b1961a9d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm or SEO manipulation tactic. The ML classifier also flagged this PDF as malicious with high confidence. While no scripts were extracted, the presence of multiple external links and the ML detection indicate a malicious intent, likely to redirect users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://irlanc.ru/uplcv?utm_term=saxon+math+course+2+pdf+free+download PDF link annotation
    • http://moneymaker-gold.de/files/20460659541.pdfIn PDF document text
    • https://andrejc.si/files/file/72334692948.pdfIn PDF document text
    • http://sdds.be/userfiles/file/velasutizuvenuno.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c683e14ad8---vowus.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/b7gaaal4ske4qov7ibl0s73ri3/8641950125.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/od8sj5235pgm6s32tg7148jfjr/zobejimimixomobapolaj.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/fejurewugo.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/60112270926.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/kbnkjugdnrsfl5vsftvbum0jom/tatotuxinofuv.pdfIn PDF document text
    • http://elite-nails.pl/Upload/file/ripimotudoza.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/nmto4hsprna5e5bt3jn5pn6h8k/ratajalejiwajasoze.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080995c084b0---kebegib.pdfIn PDF document text
    • http://osc-pribor.ru/products_pictures/file/fejodefef.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/sinurijekis.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607afa88677c6---10979105840.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/lijusosevuzobakep.pdfIn PDF document text
    • http://xn--h49al33a2zdp0eo1x.com/DATA/file/20210804000816.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607186c11219b---9777388603.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/sapamofepisubazemuponer.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/zuguzozijifizuzomuna.pdfIn PDF document text
    • http://harckocsik.hu/userfiles/file/36745733429.pdfIn PDF document text
    • https://bloc-immo.com/images/vigob.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f47480e26f---20520561706.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acadf90229e---94738938042.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_off000116c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012ee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE0 11276 bytes
SHA-256: 5bab6440801129781c26ca3e56a0e857ff0c216fefe372e78d74b33c0696d04b
font_02_sfnt_off00014948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14948 17768 bytes
SHA-256: 5525fea99fd382e69ce6e91e304d7a71cbb7f49d10cb425c5fd4e7e9b17a384b