Malicious PDF — malware analysis report

Static analysis result for SHA-256 9553d259ad572efa…

MALICIOUS

PDF

76.6 KB Created: 2021-08-20 04:24:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fde8ce6507cab08a9fdbbc5f6eb92da6 SHA-1: a8709d50c08ce84d834481a1c9868063fee4cc5c SHA-256: 9553d259ad572efaddaaaa8ec045eb80387ed9353379876f19279ee739d8a985
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malicious content.

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 https://chcial.ru/uplcv?utm_term=best+armor+hypixel+skyblock
    • https://baatco.com/ckfinder/userfiles/files/mupusuriwelerolaxeninubaz.pdf
    • http://wittymall.com/multimedia/userfiles/file/babusixefenurekuxixafoxu.pdf
    • http://christopherdallo.com/file/fuvemexipivurilinuv.pdf
    • http://greenbrier101.com/userimages/vutomuvuvupovemenez.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/3e5e658848cb4b05c690a49d80f122d7/lugavepotigulunekok.pdf
    • http://0965818789.com/CKEdit/upload/files/kubun.pdf
    • https://marblobathware.ph/app/webroot/img/files/19791325526.pdf
    • http://www.benyowsky.com/resources/files/24103860498.pdf
    • http://robertfeinberglaw.com/images/edit_images/file/kalimo.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d60c2f59d8e---33855838354.pdf
    • http://erpsamik.com/ckfinder/userfiles/files/tituxi.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c45cedb1c1f---60680666297.pdf
    • http://xaydungphongphu.com/uploads/files/65785635471.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/df0073342672746dd50c55bd46c6b723/duxalomobitejuwusipuwofe.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7d5e96a44b---47950660004.pdf
    • http://polkovnik.su/upload/file/jiwijabegugawuda.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/22085c0ba7d35931b0f15887ba536d06/36290718023.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082510a93214---nuxudafijet.pdf
    • https://wtmasonry.com/ckfinder/userfiles/files/gumosisoditedalowabaxe.pdf
    • http://designklasse.de/ckfinder/userfiles/files/62353571802.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/pfb7gtbt8mr6b2ko18c4qdkkpl/ruguwazosipetemofoxawi.pdf
    • http://cl-pub.com/files/files/50706399287.pdf
    • https://marblobaths.ph/app/webroot/img/files/sozivu.pdf
    • http://omonetach.pl/foto/ilustracje/file/xirosunikewuvozomogorad.pdf
    • 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_off0000c63f.bin
feb1ed92f205909ced31ae498b2cbab683e89864fe992edc8e22f1bf627f3e54
pdf-font-stream PDF embedded font (sfnt) at offset 0xC63F 16976 bytes
font_01_sfnt_off0000f2a1.bin
b8ce8c9e285a5d29707b717ba3c465c9f006b9dba1a040a240b7b7611d17b6c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A1 11036 bytes
font_02_sfnt_off00010c39.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C39 16792 bytes