Malicious PDF — malware analysis report

Static analysis result for SHA-256 871a51542f28cf62…

MALICIOUS

PDF

78.7 KB Created: 2021-09-01 21:14:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 7faa83afffc7e2cbb25beef85706f1e0 SHA-1: 1b2c48fd5dd1569bc2419c699b520304409fbad8 SHA-256: 871a51542f28cf6270590a51f82b6780cf77551ac1cca8eef89191d0f487101a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6197

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9ae12acecf---nevegugewunozakasafe.pdf In PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/4jbcu18vk4ab0j9g0g106uhhf7/janupepasinatekuzo.pdfIn PDF document text
    • http://hanboo.cn/Uploads/file/2021061204004670554.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/70631798145.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/judatepa.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/1fc44bf4a424996f807e4c39b3382fde/47599996329.pdfIn PDF document text
    • http://cl-pub.com/files/files/27693531514.pdfIn PDF document text
    • https://sinarwaja.com/account/files/zuraralitamuwaruvadod.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092a17540094---dumete.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/votagututovumo.pdfIn PDF document text
    • https://wavesmaroochydore.com/wp-content/plugins/super-forms/uploads/php/files/5sscfgjg9m61loljnbl44bd7e9/83595862587.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607a79e52f5b1---56312317584.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/27479888909.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/6eae631b0b4df6ca51eb20930b4d2bfa/42323040138.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/5599743333.pdfIn PDF document text
    • http://proclima-membranes.ru/userfiles/file/40203725145.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f0f9385b704---logegegolasine.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0109f7b5f3---bijewufepovanusukopuxosev.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/7085b70caba327d31892dca084209cd8/gulewevove.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/ziwilobipaperesakivikoka.pdfIn PDF document text
    • https://museuminiaturesbesalu.com/files/18266445769.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bda29905850---tarovixexirasorakexe.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16074960cbe369---popodevemilifedufil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=preview+combine+jpegs+into+pdfPDF link annotation
    • 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_off0000dba6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA6 17272 bytes
SHA-256: e11607c79f12b9202d0e4dc4a3ae74d10c7794515998014e593cae8efa321d54
font_01_sfnt_off000108a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120BC 11180 bytes
SHA-256: 0c684586723fe2e3cd3aa4eb0edb0021cde7f3a2ec6d5702ddc5d23ff8c84562