Malicious PDF — malware analysis report

Static analysis result for SHA-256 426f521337080810…

MALICIOUS

PDF

87.8 KB Created: 2021-06-30 01:09:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce231e209d0cc416081369752cf73d66 SHA-1: 8f67c87065fdd92fed9358827a1ac82b51381ad3 SHA-256: 426f521337080810330a4b9f78094808b5147b1bea3ad259c2be41dbfb1c377b
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond what is inferred from the heuristics and URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 https://majubesar.org/contents//files/darakuf.pdf
    • https://sahyadrisevasanstha.in/userfiles/file/17138587466.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/g7tgibodbvh4a68jp599ab5760/likakodewemiwazo.pdf
    • http://stroisvias.ru/userfiles/file/82039095882.pdf
    • http://sam-global.info/files/file/34981645709.pdf
    • http://autodilykanka.cz/cmsimple/images/file/totimujokuvulaxoti.pdf
    • http://zuche0551.com/upload/file/41316485068.pdf
    • http://uceng.net/_UploadFile/Images/file/95400028714.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/36pvv4fe4m1nmvrjhk5t26jrm0/jemamaxeziworelovuz.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a874633db5e---14030512585.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/8e3haq5v3irft4ngig2gpdab80/saxitupeb.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609015366d448---mozubofukesovedororibimow.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/1956f225af522065f3b06cb3e776f10a/nifonupigomakenobifuzu.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16098395368bc0---99939983018.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/84d789f25b2cb303c670d7f9e5608200/walutexomaje.pdf
    • https://serwisnawigacji.pl/userfiles/file/42176726837.pdf
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/fa57a0c89dce4deddc35372bd32ba265/mujazejemuvamajaw.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608af695ecd0c---nomunijaxuwo.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/12la9hi46fq3eusqcps7697hr5/faruj.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/a95ff4187068d416213e795cce09ea81/49883542576.pdf
    • https://cowichanmusicfestival.com/userfiles/file/suxopijinajuniwi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=beautiful+places+near+me
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4f2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F2 16792 bytes
font_01_sfnt_off00010d04.bin
f4eb1f2270280f02aa787f3ea76134522b2d89f3cc5c72446426dcfa4f134310
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D04 17632 bytes
font_02_sfnt_off000139d4.bin
63b1bf1ba444b935775de2038e7332ef29e0e439caef019b7dee91458acac342
pdf-font-stream PDF embedded font (sfnt) at offset 0x139D4 10676 bytes