Malicious PDF — malware analysis report

Static analysis result for SHA-256 442436a640781163…

MALICIOUS

PDF

80.2 KB Created: 2021-08-24 20:27:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: e6dbc8395757e521b94b309aedf8b421 SHA-1: f580588685ba63a7d6d97eb23768a473c10deab9 SHA-256: 442436a640781163f971807fa1895a882ddd72cb424f297feec5c78616d7b0af
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 0.9995

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://119hero.kr/userData/board/file/56914035520.pdf In PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/octc3gkec5ol25gk2maab0atf5/jepeboro.pdfIn PDF document text
    • https://sealordhotels.com/ckfinder/userfiles/files/58980685202.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086276f1e844---maranexemabogupidadakos.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/zudedit.pdfIn PDF document text
    • https://anyimaker.com/upload/users/files/tapurelazuririfogerupetu.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/2321fd9ccc2ba546587a7cfb550562c8/30173677706.pdfIn PDF document text
    • https://birotex.rs/images/files/nipifelanusiburix.pdfIn PDF document text
    • http://ippon.lv/uploads/File/18616083014.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/89261242585.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/pivixijun.pdfIn PDF document text
    • http://stagelight.pl/userfiles/files/jalalejavuxif.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/lijabuxabafevujuzenadi.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/lenurinutetatatigofi.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac28a88c7b2---46295623382.pdfIn PDF document text
    • https://fier-forjat-valimet.ro/ckfinder/userfiles/files/88466061215.pdfIn PDF document text
    • http://wernitznigg.at/files/nonokutovideronotofebudu.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/25537533990.pdfIn PDF document text
    • http://adbuffalony.com/uploads/files/34695969126.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/4d48af7a70cf4cc8ae49fa192b730010/50287033298.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccef95d537---betefiroriz.pdfIn PDF document text
    • http://fotossc.pl/_files/file/89508685236.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=scaling+a+fish+with+a+knifePDF 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_off0000d844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD844 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f05b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF05B 10648 bytes
SHA-256: a879ea745e9678684aeb0b11d90d632c4b90d5c37635a02fc5746430fd1f2f0f
font_02_sfnt_off000108bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BF 16376 bytes
SHA-256: 9b29b6dd8f764c0f42fe9913dd3e34a1c09dc5b3d8d1c64efdbb234b1010de39