Malicious PDF — malware analysis report

Static analysis result for SHA-256 a05ab82736d5ce09…

MALICIOUS

PDF

69.3 KB Created: 2021-09-29 11:06:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53593feb1ccc934bbbee3c223e03b943 SHA-1: 9be28c70249f3ae182da4c5f5e75f3a37ce11ab3 SHA-256: a05ab82736d5ce09cbc08ec529b1f1f1075477d1a258478fd82687a368ba9863
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream, which is a common technique for executing malicious code. Multiple URLs were extracted, including links to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The ClamAV detection and ML classifier further support the malicious nature of this file, likely acting as a lure for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=mobogenie+for+android+free+download
    • http://clickvay.com/upload/files/26650580143.pdf
    • http://directopinion.biz/uploads/FCK_files/file/tixisiwimogokekinawod.pdf
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/sifumokipeminiresagekogo.pdf
    • http://pegastelco.com/pictures/files/21771787946.pdf
    • https://pt2-turbo-j3t.com/contents/files/88648437021.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/161362f1ae4dd6---36229814547.pdf
    • https://penzehir.com/dorceiys/ckfinder/userfiles/files/31572623268.pdf
    • http://weilandvloeren.nl/fckimages/mumid.pdf
    • http://hadt.vn/upload/files/78529173950.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/ff8b694560b46c55b0b4b325abbd6df3/bufonabokozebevidiza.pdf
    • http://vo23.ru/upload/file/tadafigosole.pdf
    • http://baikalspring.ru/ckfinder/userfiles/files/44624903008.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614819ba9aedb---8002105376.pdf
    • http://kutyasturak.hu/images/files/damitiwifobikiz.pdf
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/65472718342.pdf
    • http://rustproofingottawa.com/userfiles/file/423633843.pdf
    • https://hefcom-hydraulics.com/ckfinder/userfiles/files/44272761610.pdf
    • http://mindatpeace.us/uploads/files/nigiredimudura.pdf
    • https://www.alitec.es/js/ckfinder/userfiles/files/vivoru.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/73529647605.pdf
    • http://hrt-foto.hu/_user/file/17268410431.pdf
    • https://bacninhonline.com/webroot/img/files/xutuluk.pdf
    • http://aranysolyomfeszke.hu/editor_up/jezifolowowajibomepaz.pdf
    • https://giolog.biz/images/bulk_images/files/18268728613.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_off0000b24e.bin
1fe19d1be27cc7f8c53df5aed8e34bcbf9fd8a7f9e516fd20b85741dc0da17cc
pdf-font-stream PDF embedded font (sfnt) at offset 0xB24E 14780 bytes
font_01_sfnt_off0000d76e.bin
e1a4f8e2764bcca4f78189dc3357347a9787ed3c9ed844ed3b167940a68fd7a6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD76E 10480 bytes
font_02_sfnt_off0000ef2f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2F 16792 bytes