Malicious PDF — malware analysis report

Static analysis result for SHA-256 833fa12d3c5f6745…

MALICIOUS

PDF

74.0 KB Created: 2021-09-02 17:10:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e25d511cca2a8b957d49304a5cac36f6 SHA-1: 53759504934e5fff37083534b6ee90df181d5029 SHA-256: 833fa12d3c5f6745c627a94031b53c07e0eec314c5e96cfc1c8cc558fb3cc140
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8257

Heuristics 5

  • 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
  • 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://taiwanglassgroup.cn/userfiles/file/96357787497.pdf In PDF document text
    • https://dgssu.com/upfolder/e/files/20210629084526.pdfIn PDF document text
    • http://waypl.pl/upload/File/93679363740.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160858b8db135f---fuluwupukosiwiburi.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/bfd8d42f0ba66559d1069b4ee47a7cf5/fijaxibotozufatevupibawa.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/ruduzisasuxuw.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/27260150042.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610799447478b---16933790167.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ab7c7c627---14702415700.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/15525973596.pdfIn PDF document text
    • http://www.benyowsky.com/resources/files/21729480900.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/joziwadimalejuriredobagub.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/dd7f1a8ec43f88150e799ce7bb2afd1e/40111805584.pdfIn PDF document text
    • http://ylphs.com/ckfinder/userfiles/files/nepunipizejod.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/32721639482.pdfIn PDF document text
    • http://www.majbrno.cz/uploads/files/pofuda.pdfIn PDF document text
    • https://mclarenquartz.in/ci/userfiles/files/zosem.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/92247199720.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/08/22/xumizowa.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/komezinutorevagasozem.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/gigoseredexozelulumili.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/ee7b2c15410e900555dd0d7a3818cee3/82985994871.pdfIn PDF document text
    • http://learningkey.org/userfiles/sutofexulififunefinubem.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/tolevemawefagupelagax.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/77a5082208fac48c0dd30acb4755f945/81168324821.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=financial+institutions+and+markets+pdf+notesPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF406 18508 bytes
SHA-256: 8ab2ccc3659a6fe7a4838a2a847f3af4025f89f37cc7c4be977976647da8e949