Malicious PDF — malware analysis report

Static analysis result for SHA-256 0533c937ba7d857a…

MALICIOUS

PDF

86.2 KB Created: 2021-08-20 15:02:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8ae91cf21ca758f8e4d4c3f25fb570ab SHA-1: 38b2bdb7dce6d9b5af5241fd06ae9859abdc153b SHA-256: 0533c937ba7d857a14d58f16921be67966122ddaa34dd268879c30a6843bc1da
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://queure.ru/uplcv?utm_term=what+does+the+name+schatzi+mean
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/80f2a18deef0270616f5069ee67d83f5/neletezebewomepunob.pdf
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/35ebd40d12dd6178f834bb776ba8f45c/88442467246.pdf
    • https://xosobacninh.vn/webroot/img/files/51942167744.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/ce59697872f3c4ef2cff2dad262dc462/nimubizunisigawijexofaf.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/775973d67ae3274c76a700035a887b0a/87255000409.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e507b9063---6552461911.pdf
    • http://box8websites.com/ckfinder/userfiles/files/panivojodulonuj.pdf
    • http://lab4050.com/upload/editor/file/35913309813.pdf
    • https://psychologgia.pl/Upload/file/52883637202.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609def43d25cf---64742983392.pdf
    • http://snft.ro/media/file/51996644939.pdf
    • http://cherryontop.pl/upload/fotki/file/91585650265.pdf
    • http://np-laser.com/upload_fck/file/2021-7-7/20210707223405325219.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/1nl60o503kirrisimjbb37s157/93116964463.pdf
    • http://agiusfuneraldirectors.com/files/file/vupodejujowamakegusit.pdf
    • http://holidayinntorino.com/userfiles/files/mesisetiketesamezino.pdf
    • http://gordostcrista.ru/userfiles/file/wakis.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070d91ba7975---kixujokijomer.pdf
    • https://congtydaihai.com/upload/files/7307949426.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/07cfd141b2c51adece6656eb2a7ed301/vulutinoxiza.pdf
    • http://architettoangeli.it/userfiles/files/22053726844.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846083c859a---nurazirenukofovozotelafe.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606cae14a926a---32552235327.pdf
    • https://rosewoodcity.org/nbloom/fckuploads/file/nawafotokukizago.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_off0000ed5e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED5E 16792 bytes
font_01_sfnt_off00010570.bin
42604260b08c3d4e9804d169b3c5d2f69443a7c76417932e6efab203da39ec95
pdf-font-stream PDF embedded font (sfnt) at offset 0x10570 17584 bytes
font_02_sfnt_off0001330c.bin
f9a8a2c36b85947c6f14e37a86e6c6e9412ab80195f57793620301c8688e1207
pdf-font-stream PDF embedded font (sfnt) at offset 0x1330C 10540 bytes