Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c1478b3c1098fe…

MALICIOUS

PDF

92.8 KB Created: 2021-09-07 12:09:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d6a20525a6bd099bdeb0ccec04e69f71 SHA-1: 1cdc9936cc84a9b704afcebd9dea21a5137edddd SHA-256: b5c1478b3c1098fe523009a4cebce39b5ebf69a0f23203db30c83964b0c1e480
156 Risk Score

Malware Insights

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

The sample is a PDF file identified by ClamAV as Pdf.Phishing.Trojan. Heuristic firings indicate it functions as a link farm, directing users to compromised WordPress upload directories. The ML classifier also strongly flagged this PDF as malicious. While no scripts were directly extracted, the PDF structure and URL patterns suggest it is designed to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a56c46efaec---66138933131.pdf In PDF document text
    • http://cariboohose.com/userfiles/file/pufaxaxeluzegokoxol.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/d4253b9d5131bd678735a5471490c3fc/13698118279.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/i7q9jf2kja9ccnbqe4flii7sf2/27513967247.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/27900400305.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/5c5auhh8l9h369i94g41amau87/58453755929.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d00980b763---tobumirasi.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/32861031676.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/wekimil.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbb2d4585c2---wufisewapopebuvaxof.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16073f1dee2e05---mokesexanudoguz.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/95105361506.pdfIn PDF document text
    • https://iwistw.com/upload/files/xudefopapogapur.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c291fbaa7d4---zenaxogotukasiriv.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/373ec2da113dd73299a93347be0ca97e/lamowakavojaz.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/4b001af33ffc083dc491feee321f889c/boxirito.pdfIn PDF document text
    • http://oio.cn/uploadfiles/files/65374750556.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/tiwojajegonir.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/95856967402.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16076a15c7cf64---zixozodew.pdfIn PDF document text
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/54085641929.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f97bf4d58c---logiwepoxomoxup.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/q3fscjg5ev7ip07nmc8mfchsfj/daxezipoxomajov.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/dpvgkafvr4emjqhsqhksu0nsuc/66310722761.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608faa44da98c---kipekineluwedawumuzesi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=radikalisme+islam+pdfPDF 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_off0001057e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1057E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011d90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D90 18960 bytes
SHA-256: 6e9191ef6111736288176872a0376e4b5b3d4acf7d9bb4030895e6a01f195f55
font_02_sfnt_off00014e89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E89 10372 bytes
SHA-256: 67dc050ed075b0772293d787f607ad47ce541f4deb09ce9377cadff421a308ce