Malicious PDF — malware analysis report

Static analysis result for SHA-256 837d45c4c0ce6e7b…

MALICIOUS

PDF

88.0 KB Created: 2021-07-21 16:04:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6d3f9acf00166a85d0bd1ceeecc66805 SHA-1: 32f7f1ce79dbb7309f1f67208a7a5ad5278ec40f SHA-256: 837d45c4c0ce6e7b68862a4ca0ecd0ca87e118bd85eae74e7ea41ca9bbfb4ada
156 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The presence of numerous PDF links and the use of 'utm_term' parameters suggest an attempt to manipulate search engine results or lure users through deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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://lookkorea.net/userfiles/file/wajew.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075fe8ad34d9---25750905114.pdf
    • http://muzycznescyzoryki.pl/userfiles/file/sezakudegesadeveseposu.pdf
    • http://pleasanthillpchurch.com/clients/5/55/55aa087cacc886b2254ddcc242c0699b/File/pobez.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160850b5f4671d---10793788096.pdf
    • https://scapetime.net/images/website/user/files/sotoxikorumubexugeguso.pdf
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/dc2931e10a62c19c74da57e761a96be0/65300212045.pdf
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/p2v99qrjbjspdbl337t2pgm41q/79858186647.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c434048290---86104874639.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a618a8b19b---316996835.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/821b29911c7eb1c27cb02ec6ce5c084a/lujomugo.pdf
    • https://agmatbaa.com/upload/files/jojixo.pdf
    • http://donateagift.eu/userfiles/file/13229026752.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa8541fb67---risagivefiviworo.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb5025a43b---tonutef.pdf
    • https://aawyx.com/sites/default/imageuser/file/papotelululi.pdf
    • https://advantagelic.com/singhania/downloads/file/nepupetal.pdf
    • http://bangkoksolarpower.com/syner_upload/images/files/vikub.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609314a01e61c---20706590365.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/b92317bdf7f0df8800b4a5eae7b6493d/25731392935.pdf
    • https://alnahamgroup.com/userfiles/file/jogojotogiloxu.pdf
    • http://amdind.com/userfiles/file/67828631722.pdf
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a090e79c7c4---rulikomazepesijobubog.pdf
    • http://trunglam.vn/uploads/userfiles/file/54242482990.pdf
    • http://jogforbigt.com/clients/6/61/61f7a61d17da296148a50ccd59c4a139/File/3487937288.pdf
    • http://oilmachineydy.com/d/files/xotetoxigi.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c51b33d20cc---limotokedov.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+clean+plastic+electronics
    • 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_off0000f65f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF65F 16792 bytes
font_01_sfnt_off00010e71.bin
c9b5c113f0739ef583fd89c09463de92be761e8503eaa1565ba13fb376b36c43
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E71 16456 bytes
font_02_sfnt_off000138dd.bin
7a7bb977ad4597e8b1adff002e502370eb3701637146f259f2f0c55171df9631
pdf-font-stream PDF embedded font (sfnt) at offset 0x138DD 10444 bytes