Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa528823d13e652…

MALICIOUS

PDF

76.7 KB Created: 2021-08-05 16:42:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: eba235c4d5fa1fc74dee75cab50f45b3 SHA-1: 1d4d5b2d8fc56a8bec494fa4002d81d9f318cf34 SHA-256: 4fa528823d13e6523e2ed778142097b0550feedbec810ebee2ca60bf2f083414
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting it functions as a link farm. The presence of these links and the PDF structure strongly indicate an attempt to lure users to external sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://tylincms.com/userfiles/files/38644840621.pdf In PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc132aa1d9---wezarojoluna.pdfIn PDF document text
    • http://davidlbrooks.com/clients/868292/File/78692422986.pdfIn PDF document text
    • http://sowitech.vn/upload/files/mixodatigomop.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/kararu.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1cf67782cd---libijalejogapegusam.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/f668d6f0f40cf1bd1e6935abc3d3eaec/96010515841.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607de51269f1d---mukese.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080d5f508bcb---tofumulazufanofega.pdfIn PDF document text
    • http://koreanhotpot.com/uploads/files/rinaralelifa.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/kdughv3r2reb774ulripne9pkk/salojibe.pdfIn PDF document text
    • http://kino-cosmic.ru/sadm_files/25912118030.pdfIn PDF document text
    • https://rjpexport.com/files/gejorivajogabodivi.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160848dff9771b---71551619805.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/sivusejatu.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076166629c03---jobililapezifas.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/19345984752.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/85073788081.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/a1f068fc6a02e17c4e5ea5878e4a5a37/kimerepupole.pdfIn PDF document text
    • http://gloexdr.com/wp-content/plugins/super-forms/uploads/php/files/d4cfbd1ddbcf9ee526cf2dc1d3920986/75651954814.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944fe4a11d2---vetopibisadogemuxuzanisof.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e267888613---juxezujarixilinene.pdfIn PDF document text
    • http://teechart.com/uploads/images/files/69838088517.pdfIn PDF document text
    • http://ssanadia.in/userfiles/file/7790229957.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=astm+f2792-12a+standard+terminology+for+additive+manufacturing+technologiesPDF 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_off0000c545.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC545 15880 bytes
SHA-256: 26c6501e8ecc095df69d0a0873e93606701db4d228c1ed3fbd46f1557b358f63
font_01_sfnt_off0000ee45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE45 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001065c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065C 11608 bytes
SHA-256: ca0f52202a774ec53b654562fd65527572022e86c7f4794727290833fa2c8a9b