Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8449be3d68c38f9…

MALICIOUS

PDF

78.0 KB Created: 2021-07-04 19:34:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d71737dd59c0d3111f7e6e9167fc7aa SHA-1: 6a551852188d22be961696e2ab8c7658fe25bd20 SHA-256: d8449be3d68c38f9c6827ee43700dd515bf441697526f8f9c0221b01044f0480
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the nature of the links and the PDF structure point towards a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=read+brian%27s+winter+online+free
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16095dfdc05732---bavokibominubomeviji.pdf
    • http://zs-oilfieldequip.ru/d/files/73589320112.pdf
    • http://steakclubhn.com/campannas/file/34463583162.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfd8df4e9ed---wenizokamunux.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e06861a2930a06fd52f0a36e29077f6f/84601189389.pdf
    • http://www.cerathai.com/image/upload/File/27917730858.pdf
    • http://poiskvod.ru/images/file/rapolibibawivatixitafokol.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085cd486e79f---wojanisopebezisololezevox.pdf
    • http://akinmedikal.com/uploads/file/64924400162.pdf
    • http://zonwering-nederland.nl/ckfinder/userfiles/files/zokadisesileb.pdf
    • http://sake2metustin.com/uploads/files/telarodumusutifikeje.pdf
    • https://kis-u.com/page_data/file/20210620095949.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c37838ee7---geruwixabunotuwugopezawa.pdf
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d36d319b3---58092657165.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/1ndkgfhojea64n6p44grk8ccdu/tiwakumaxa.pdf
    • https://aawyx.com/sites/default/imageuser/file/tidubikipawiva.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/46cd2571759ceaaf6e5100c448bb8955/wakuwikuxinoboleleke.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/04ca48a980335a4d84a77ad0acc9e7b8/8131901533.pdf
    • https://foundryindia.org/userfiles/file/12751802537.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/950decf1ee84c580dafa6c2feac2a5f6/56712588094.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084eefac062c---2571819747.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_off0000ce64.bin
c9997acffb6f89ccf221c3967d2d3e661dce98e91233b71b9dc55626388d1fbb
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE64 10652 bytes
font_01_sfnt_off0000e6f3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F3 16792 bytes
font_02_sfnt_off0000ff05.bin
a9a9ed2cca903becd390d361db8175b46082f4b23093dfb311cc9dfd795d1d78
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF05 16944 bytes