Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b0d2256d341c4d…

MALICIOUS

PDF

70.5 KB Created: 2021-09-02 06:21:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 985f8aad3e51355b06af1c8976ef24f2 SHA-1: d5f53fe3cddbe5d5a8cd0da34a99077f0ad4ee93 SHA-256: 77b0d2256d341c4d601b20f424818483789ef105566324943672eb02413a0b98
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious. It contains a link farm pointing to multiple compromised WordPress sites and other disposable hosting, suggesting an attempt to redirect users to malicious content or phishing pages. The document body is heavily obfuscated and does not provide clear textual content, but the heuristic findings strongly indicate a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nesthomes.in/userfiles/file/71556456759.pdf
    • http://wronba.com/uploads/wysiwyg/file/59415727741.pdf
    • http://haciogullari.com/depo/sayfaresim/file/gifixigegosavuwugalunijat.pdf
    • https://medprobr.com.br/wp-content/plugins/super-forms/uploads/php/files/1657ab08dae5739f92848ffd4c64fd51/luditirokukomixilezi.pdf
    • http://przyrodnik-kujawy.eu/userfiles/file/35767261222.pdf
    • https://kfk-dekoration.dk/images/uploadedimages/file/zezirulirivujewa.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b519870a43---jinokidogemuxejejo.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/p3roo551tqqb4ukorr0qaj4pb8/vofeligojibovojevixumera.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/a15fdea6ca157704ff6490d1129527a7/pizukajoro.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c13ad14cad4---gakopisekobos.pdf
    • http://griesvoegwerken.nl/UserFiles/file/dobakoxeximagidunowul.pdf
    • http://alpanelektrik.com/depo/sayfaresim/file/44893457146.pdf
    • http://broadviewlibrary.org/uploaded_bvlib/file/26776362646.pdf
    • http://goksirkrupskimlyn.pl/img/upload/files/88681449760.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919d8b102d6---32569754654.pdf
    • https://t2sc.me/userfiles/85631970146.pdf
    • http://eltonltd.ru/sites/default/files/uploads/1963087533.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16097fc716852e---zimaf.pdf
    • http://telmeed.com/web/ckfinder/userfiles/files/nemon.pdf
    • http://coreaad.com/DreamDataUpload/file/bamegadon.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=minecraft+how+to+farm+nether+wart
    • 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_off0000b541.bin
53d7619fc8bf0648c5830963b7fb00b6bf9b1461cd204b486da2929c38dbf0fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xB541 15400 bytes
font_01_sfnt_off0000dc40.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC40 16792 bytes
font_02_sfnt_off0000f457.bin
5638ca5871630ae9e31481434bc8adbf54734e58c19e641284951818b5788599
pdf-font-stream PDF embedded font (sfnt) at offset 0xF457 10464 bytes