Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d70d5af3767b581…

MALICIOUS

PDF

76.2 KB Created: 2021-09-17 13:03:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 74834f5ecb23a151510ee2f30ff71b05 SHA-1: c8daa8611058abffa163503686ce0bc2566a4cda SHA-256: 7d70d5af3767b58125154e6441403b228f30755bee8f5403d657c2b30fb96a13
124 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to files hosted on compromised CMS uploads or disposable hosting. The ClamAV detection as 'Pdf.Phishing.Trojan' strongly suggests malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not meant for direct user consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4750

Heuristics 5

  • 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
  • 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://tonmathunglan.vn/upload/files/9155998856.pdf In PDF document text
    • http://berbun.com/user_img/file/jetetakimumomotoveruvat.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/06ooivub4a4obe6j20gouctmt0/jezovuleragoku.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/zibor.pdfIn PDF document text
    • http://kezmosas.hu/files/file/waluges.pdfIn PDF document text
    • http://gro-felix.si/uploads/vatugukesuwa.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142363b0b1c0---95017026389.pdfIn PDF document text
    • http://kelakewangshangduchang.a9188.com/upload_files/art_files/files/20210911_044857.pdfIn PDF document text
    • http://emeat.ru/var/files/3411691077.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210904_082333.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/60042281481.pdfIn PDF document text
    • https://betsin.org/userfiles/files/44132203948.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/nexepawowapubipasobemu.pdfIn PDF document text
    • https://shaplaconsulting.com/app/webroot/ckfinder/userfiles/files/bibixedewupadejofabido.pdfIn PDF document text
    • http://resurrection-life.net/userfiles/files/36618783103.pdfIn PDF document text
    • http://wellgroup.cz/UserFiles/File/49132522907.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/14455479390.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///gabik.pdfIn PDF document text
    • http://be-now.pl/userfiles/file/ximulonume.pdfIn PDF document text
    • https://urology-andrology.com/userfiles/file/mitabom.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/timedaduselosubefafomisez.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a7cebd2fd---9581103522.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614286e3da6f5---19943380304.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/tofolazadujuba.pdfIn PDF document text
    • http://centronegozi.com/public/61409947253.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=ac+rebellion+apkPDF 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_off0000e3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F7 17996 bytes
SHA-256: 39da5aa32738ac4827c6a23f4bece326aaab530d17148be77c63492ae5423008
font_01_sfnt_off000112e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E7 10316 bytes
SHA-256: 9cd8a108db817a58d26a011b4a22882e33a9890bda844e0ee82837da37767176