Malicious PDF — malware analysis report

Static analysis result for SHA-256 2e24831c159e6f35…

MALICIOUS

PDF

96.7 KB Created: 2021-06-26 04:17:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f021e27da4640eab744f6647be7beeed SHA-1: 25c68d8420beeea08d642310a508f38656cb4623 SHA-256: 2e24831c159e6f35097ccde7603d819367ac8fac28113eaa49f504c62366aefe
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised WordPress sites, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be metadata from the wkhtmltopdf tool, rather than user-readable content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://medvor.ru/uplcv?utm_term=red+goby+fish
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7eb92ab7f7---29793174312.pdf
    • http://lacyfamilyunity.com/clients/2/20/203fd950dafdada58ea32e7b96f0d147/File/38718285478.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/7irq5scfd6g5ii09mp40cjtrt5/72374620581.pdf
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/aae62593f282fd7b8c3f043fa5df7138/5460822393.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16076aad106f1e---73317857603.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b1d23b2a1---rixulemolejinetipozuza.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160859d4796b4c---18194060703.pdf
    • http://constantemails.com/userfiles/file/1624067783sekezibemegororanoli.pdf
    • http://labonscafe.com/userfiles/73094582848.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608068c225fb1---latuvizigepunigimifuf.pdf
    • https://bostoncake888.com/UserFiles/files/fapogikuxepaginegevav.pdf
    • http://slenderclub.cz/ckfinder/userfiles/files/76396934354.pdf
    • http://rustproofingottawa.com/userfiles/file/texesalitotovevor.pdf
    • http://xn--80akazwaeiw.xn--p1ai/editorfiles/file/17699911967.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/ehji9jr0tlevq0as32djalbggp/21157641712.pdf
    • http://altelaw.com/uploads/image/file/ruzetoroxisekemaro.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/456df8c762438d092bff0ebd9e18b450/rolulazimusuwovob.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cad3d8a3399---29006915222.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9c5932f6c---pimixorinijivolobo.pdf
    • https://amursvoidom.ru/media/files/94551753994.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/72ba9d8cc435193aab792061fbf6e868/43183769542.pdf
    • https://facades-et-traditions.com/actualites/file/47273790757.pdf
    • http://haiphongcontest.com/images/files/96367291432.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_off00011938.bin
defd772d21ba706c037ca8a9ad9d937703e5b3b583d8a26bec575c8253af7b7d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11938 17276 bytes
font_01_sfnt_off00014673.bin
c44308bed06221cead6247b52f3741b7966fcbc9ed33e570ab5fe882869b5fef
pdf-font-stream PDF embedded font (sfnt) at offset 0x14673 10420 bytes
font_02_sfnt_off00015dfe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DFE 16792 bytes