Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b165bd108761b5c…

MALICIOUS

PDF

91.6 KB Created: 2021-08-05 11:41:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: dfffc88e61def0e1b46480dd14911b87 SHA-1: 1d35c20fec7236503fdef25ad260b8eb14178d17 SHA-256: 4b165bd108761b5cfe34322dff961f5e9e7f3f4a260a56a35603b450ced98ebb
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised CMS platforms or appear to be disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically classifying it as a phishing trojan. The primary attack pattern involves luring users to click on these links, likely leading to further malicious content or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://tpokebar.com/uploads/files/nenefuxepotabamabava.pdf In PDF document text
    • https://mbbs.hr/files/94103180419.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/v0v3ijj5c0ae8lrkpipkiao1po/juranirejusul.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/69042730948.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/99738176501.pdfIn PDF document text
    • https://qpshouse.com/upload/image/file/7241496263.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9d0ea37a4---71604572909.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d2800572261---86197216979.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/rufopujafigiziwuda.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b52658b6b36---wemozurorunubukakoxof.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f71ae134c12---nopezorelotevexa.pdfIn PDF document text
    • http://kutscher-customs.de/gfx/userfiles/files/xaminidunuve.pdfIn PDF document text
    • http://mesterek.net/tmp/96178702753.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/ba34c37eb3fe0353b8378b566ae02c61/lebujorinevipowi.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/82873fe3ekp38ncn9c22qnrgrv/68604922424.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/6111332147.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160c226a4db41d---ramigumunefoxep.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/inl1d5rq3ge7dt3aenbo9aouk6/43706753487.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/29549213172.pdfIn PDF document text
    • https://loctra.net/userfiles/file/masemukijogexiganotigezuv.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/rikogivosipofemegeluno.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/f74321f8b8b193a43d54a3bc0f696d58/xemotalegizizuxomo.pdfIn PDF document text
    • https://drinkpoint.com/uploads/files/kofatugopopudaw.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607904cef0d1f---padofi.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/51939721380.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=preposition+worksheets+for+grade+3+cbsePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001022f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022F 17132 bytes
SHA-256: 559d230e7dd1ee0e8acc92841e42ad5ec70bbd1aa3bcaede87249c9de9e727bf
font_01_sfnt_off00012e35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E35 11344 bytes
SHA-256: d8a8687c6f879ee0757dd2924fd975e517bdd7b88f84235ec952691a1be12983
font_02_sfnt_off0001488b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1488B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1