Malicious PDF — malware analysis report

Static analysis result for SHA-256 819d1fa40847bc86…

MALICIOUS

PDF

80.8 KB Created: 2021-09-12 20:01:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: af16f557b8eb6726904a01eed8103c6d SHA-1: b8f099b25a52aa7579fbe797acaf45b011f6ad49 SHA-256: 819d1fa40847bc86b301ea40774d8f0e0f6ff6aa902244c775d7ff3db0484883
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised websites or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO manipulation. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://autosoftware.company/autoresponders_images/files/ninaragipenedamarejopare.pdf
    • https://juraganmonyet.com/contents/files/doxebidejugogatejir.pdf
    • http://portakalweb.net/home/portakal/public_html/ckfinder/userfiles/files/41676608371.pdf
    • http://sevvalturizm.com/rsm/files/44749788714.pdf
    • http://wawabed.pl/uploads/userfiles/file/pevutidorutekegejidagufi.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/i44r9n14d4o2deq4g4q2ivemtd/lubudufirej.pdf
    • http://mmckno2010.zkosuchdol.info/files/dexafidulikix.pdf
    • http://abwvictory.com/uploads/files/nutabipu.pdf
    • https://shen-su.eu/gfx/userfiles/files/3078457343.pdf
    • http://safetyassessmentsolutions.co.uk/ckfinder/userfiles/files/salefepaxakuka.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/2958f8a830f60821b7d11dc292d7dc5e/58598106209.pdf
    • https://academiapreprod.riportico.com/userfiles/files/sutonupudefe.pdf
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/19447002331.pdf
    • https://xebecdesign.com/xebec/userfiles/file/sogisafe.pdf
    • https://tsegypt.com/file/gidusilijivemusewonubef.pdf
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/guxebedagekajowez.pdf
    • https://kozlovka.mebel18.com/uploads/files/wirofarisovukoxege.pdf
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b71ab0c78---75950251282.pdf
    • http://irvine.songhakbbq.com/uploads/files/98422585834.pdf
    • http://mrcookie.tw/upload/editor/file/081211441415.pdf
    • https://szemvidito.hu/sfwkr/feltoltesek/Images/Image/mazabezenojanaxuxakuw.pdf
    • http://automyjka.pl/automyjka.pl/userfiles/file/60881711889.pdf
    • http://tdjl.com/uploadfile/file///2021090802122199.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=bubble+shooter+flash
    • 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_off0000d8a3.bin
5adf941614967b71a74855a97c6e91beb2b09724aa9dbf6b1317a359347a55e7
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A3 17480 bytes
font_01_sfnt_off000105bd.bin
7362dfb743211d1dc89952c12de34f5939e3cee0cabcab4263efb8666da047e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x105BD 10408 bytes
font_02_sfnt_off00011d88.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D88 16792 bytes