Malicious PDF — malware analysis report

Static analysis result for SHA-256 58d39b44db66dea9…

MALICIOUS

PDF

86.1 KB Created: 2021-09-04 04:12:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cbfdfb47c323e840e4a14237539bd9fd SHA-1: 6497affba4fa73492130849582d19746a0181375 SHA-256: 58d39b44db66dea96a60273844a9752646349eb7e640ca64a63b14bddd9591d9
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple unknown URLs, several of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b23f9f04a---42164551956.pdf
    • http://agavietnam.com/img/files/78852498843.pdf
    • http://hart-metale.pl/gimnazjum/userfiles/file/wegoderevuro.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611d2b7d3cced---zedov.pdf
    • https://lee-trading.tw/archive/upload/files/rawosafivoganekasunawu.pdf
    • https://attackworkoutprogram.com/app/webroot/files/ckfinder/userfiles/files/kafadoxatefejijokut.pdf
    • http://usateatop.com/_upload/files/xenogolaneviru.pdf
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/f25e2c7bb7cc4dd3bc7e0d09e7e710bf/90348048890.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/duralenuxivaxoresedupexek.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b63412b70e---dubezusivaxezegorajurefi.pdf
    • http://lowndes85.com/clients/d/d3/d39312ffd46aa2fbcc4e4de04d96a17f/File/10431817848.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/1d0a8bf5765e3c783ca69fb9d5384318/buwekodipofak.pdf
    • http://dbexpertise.fr/catalogue_dynamique/file/jukivusamo.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/9e3f3701376c1d9cc197ac8d9ad4c4e5/zoradapiresene.pdf
    • http://planet-for-events.de/userfiles/file/kipevufamuzed.pdf
    • https://sayurmateng.com/contents//files/47278676767.pdf
    • http://afghansolar.com/userfiles/file/lusalexo.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16109ba4478853---66830145660.pdf
    • http://beccaro.it/userfiles/files/gimaxa.pdf
    • https://traveletrust.com/basefile/traveletrustcom/files/32978814413.pdf
    • https://total-sport.pl/img/upload/files/16280560762.pdf
    • https://privatecambodiatour.com/userfiles/file/rimiduzifidavexonav.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/348baf7365d749cf29c0951e3a3b675b/kadajamugo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=tenancy+contract+format+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_off0000e6d5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6D5 16792 bytes
font_01_sfnt_off0000fee7.bin
06ae30b9b2d7f81cbab9c2a96202cc00499cd058678d78cbf4b31c34e51eb138
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEE7 20604 bytes
font_02_sfnt_off000132ce.bin
61e42c39cc28a0697013a3fb2485d94ea2388b68aebf19bd82e7fe78cf20f9e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x132CE 10552 bytes