Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f55b4e1440f3439…

MALICIOUS

PDF

74.4 KB Created: 2021-06-28 21:27:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0f4a5ea11faf85857aa033c6220204bb SHA-1: 4825d96a057e0b92ef452a57bcedc39c3652ea58 SHA-256: 8f55b4e1440f3439100bd17ba79691d539c4d8eafb6323181ade35e2ff7d0bcc
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these external links. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and detections.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://medvor.ru/uplcv?utm_term=turquoise+blue+color+meaning
    • https://247christianity.org/fckeditor/userfiles/file/xosaxilenanebed1620615521.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c998ce04a12---jifomowumawo.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ac20a31e832---mepelugizuxelitokigafu.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b0e9a4d11f7---59914768964.pdf
    • http://pumarecovery.com/userfiles/files/52769926071.pdf
    • https://eravukappalpalli.com/userfiles/file/62630840998.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160abb4f5c1136---74166955271.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b681c17cbe---10773670884.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/039e5ac7158cc856b7720c8e38644314/30334675907.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160aab3a903fb1---xabadimejusebeketatojiw.pdf
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/97c7121e6bfb91d779add7befa5c2bef/65177249132.pdf
    • https://bruceleevideos.org/images/file/gudefijarepuz.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cb421cb609fe9f2e4c5a7b4fd365af92/87502321840.pdf
    • http://champagne-marc-chauvet.com/images/files/befapipifoxiluw.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160836642d785f---fisemuvi.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/779fd96aa3456b25d281854ddb9d7069/lexagitef.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/1055f9a861d0d7b4fc7fadd303c63f26/babitubimiwevuvatulubom.pdf
    • http://anandamsanyal.com/userfiles/file/53364806094.pdf
    • https://alutat.com/data/file/bazusixinixiwozijoxuv.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c96cbd7bdb---lifegirixixatolefof.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6bf5f1f800---wimilavipugovafome.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_off0000c285.bin
947bed558c38f67273581ab38479c34fa522115c7606cb452e8ccf74d6ce41c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xC285 10824 bytes
font_01_sfnt_off0000db1d.bin
e62512a806cebc93792d95048c5406c7a8f7a6fe7c30590bc59c478513f4da42
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB1D 16036 bytes
font_02_sfnt_off00010485.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10485 16792 bytes