Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b0eb9b5c300b153…

MALICIOUS

PDF

82.4 KB Created: 2021-09-10 06:15:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6d6bcc452946835943b9a67d791c5527 SHA-1: 25783f36eee7f255276439acdedeb7ed44e1091c SHA-256: 3b0eb9b5c300b1538de995c423939565db9263e6d7e28a3ee989f07a96c3b6eb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://birotex.rs/images/files/2650835409.pdf
    • http://dentish.ru/ckfinder/userfiles/files/sivazonozuxesubuxi.pdf
    • http://baltyk.recykling-rejs.pl/imgturysta/files/niderimibatamelolo.pdf
    • http://ibshop.gr/uploads/_uploads/files/40813668055.pdf
    • http://sushikyototogo.com/uploads/files/57440592422.pdf
    • https://cowichanseniors.ca/userfiles/file/93145100800.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161382e95e81ac---mefoselinegudiwadugifunu.pdf
    • https://luathoanghuy.com/uploads/files/79206486673.pdf
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/56865805200.pdf
    • http://hasomedia.com/userfiles/file/32458463788.pdf
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/rukevugusuk.pdf
    • https://aquatrustfina.com/userfiles/file/gakivexem.pdf
    • http://pazarziraat.com/userfiles/file/jatotomudegalitisutiga.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/uj5gi4flginu2e823c4h7eiem8/roxolejulije.pdf
    • https://sma-dfgg.org/site/admin/file/kunorokurofemobosipiw.pdf
    • http://fractinvest.com/uploads/file/tarubimenod.pdf
    • https://sambelteri.com/contents/files/jefuro.pdf
    • http://lagerunda.it/public/upload/file/1529737271.pdf
    • https://www.hmgfinance.com/ckfinder/userfiles/files/gutunuzuvotaf.pdf
    • http://laarakkers.com/ckfinder/userfiles/files/17631574385.pdf
    • http://longbienco.com/js/ckfinder/userfiles/files/35049561521.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/137b5f4ab891c7fb14f2d9071c80fbe8/zobupanul.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fdc86d055---luduwupivabisanazolebidok.pdf
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/42300705455.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=i+put+my+trust+in+you+gospel+song
    • http://e1pl2.nazwa.pl/busy/fotki/file/savexerubis.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_off0000dda7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA7 16792 bytes
font_01_sfnt_off0000f5b9.bin
7807ddbb527aad2ddcda28928f0fe50c5f1c9236e8fc28b8ec091cdb4bfa5838
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B9 17636 bytes
font_02_sfnt_off000123cb.bin
0f7c6440ed2cc846df5dbf50b3c39f8c0241907983580428997822aad2b8c28e
pdf-font-stream PDF embedded font (sfnt) at offset 0x123CB 10600 bytes