Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ffbac25daeb85a…

MALICIOUS

PDF

88.1 KB Created: 2021-07-02 00:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6dd493195714f6ce2005752f73247721 SHA-1: de6b3fc90e1647fdd0371731d89ec7fe8b376af8 SHA-256: 99ffbac25daeb85a91e210d1588407d01464de4c2592a8447395a25380da34cc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm directing users to multiple external websites, with several links pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://dok-vo.ru/userfiles/file/vesek.pdf
    • http://pantryscan.com/123cars/imagefck/file/kewogunasudefebaxok.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a30c7542248---69576095273.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/o8j3fa4hsi7p6s85meh9o89ocr/93421344224.pdf
    • http://jfe.hk/userfiles/mowujomagowoligimu.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5076f20c8---45019322233.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/1888a812d05dd8d8fdaea16f83525755/35290798388.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/f7985214040cf0ff8fc1ce5b02d2dff5/850075511.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087c5e1acf0b---1090736621.pdf
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d323b00eeae---zugokikoxixa.pdf
    • http://studiomontironi.eu/userfiles/files/9713259842.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/8d1e27ca673753ec5512932f0351b0ba/zanivirurekuni.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091515ed9453---88214169395.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/901b8fbd700404e409a1cf451f06d5a1/suzobunesuzisimijiguf.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b5f768180---zikatoza.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a47c09b4404---87527948903.pdf
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/jezexixujajojepe.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/19862527736.pdf
    • http://centrons.com/uploaded/file/161982433760c0afb7a3dbb.pdf
    • http://abcbyspu.com/ckfinder/images_store/files/14540298718.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/8ru5e9kccu481pr2k2lestht48/55553105990.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/c832bb19f1869e7183defea6891122b1/nubigivupavajejub.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160801cd2708ab---wujoponafilewixo.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/2bdbcd969bd2a2ffbe69afcf3be94a22/dowibesexum.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160807e5eb622f---genopebufutipiguwapegem.pdf
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/79l3f6ss113p7abc4fllrkrq06/nisotutozobakuzidotaf.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=sic+em+meaning
    • 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_off0000f187.bin
55e24e8e69d0ee07ca3b9eebcaa56d558f781d200c6426940c35ef10bb2c8f47
pdf-font-stream PDF embedded font (sfnt) at offset 0xF187 10116 bytes
font_01_sfnt_off00010811.bin
d1cf7115490c4d3cfd8e4abe677b7eb9919d0e17c23320f682072b692547bbd4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10811 19188 bytes
font_02_sfnt_off000139e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x139E4 16792 bytes