Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3a7cd8dc2d7bbd9…

MALICIOUS

PDF

81.9 KB Created: 2021-09-13 23:44:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 19335fdf5d981b2c70c78618e066e4a1 SHA-1: ce79b5ef9495a53358cf47f625521cce6ae4a4d5 SHA-256: a3a7cd8dc2d7bbd9c323602d8d4e5756fb2fd788aa5ffea0df155f7f6725e34a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external URIs and link farms pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution lure. Embedded JavaScript streams are also present, which could be used to further obfuscate the redirection or execute malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://archism.ru/uplcv?utm_term=how+to+forward+text+messages+to+email+android PDF link annotation
    • http://uni-soar.com/userfiles/file/14724304259.pdfIn PDF document text
    • http://ewtch.com/upload/files/4859282123.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135dc632c8e9---gaxegogapog.pdfIn PDF document text
    • https://generalaudit.pl/eurostyl/photos/file/88343448531.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/mivovujolo.pdfIn PDF document text
    • https://digireg.si/upload/gobabesupisavuguw.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/14661291376.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61822117344.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/sikikusit.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/161379fe6bc308---divonikupanodupipo.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/bulipaxesagilopuliwod.pdfIn PDF document text
    • http://capriololaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11392552724.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/lujekurapasexoradiw.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/6tn4jsiag54qb4atibr2bsdgh6/57444331495.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/8354431302.pdfIn PDF document text
    • http://sibinetweek.ru/userfiles/file/milup.pdfIn PDF document text
    • https://makojudo.pl/zdjecia/fck/file/nitinimoniloxosarukix.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/tagugovisaxoroxupivimago.pdfIn PDF document text
    • https://fontan-montag.ru/img/upload/5787762153.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210901_165326_1988.pdfIn PDF document text
    • http://designklasse.de/ckfinder/userfiles/files/96211167561.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/zunevuvizobexuliriwad.pdfIn PDF document text
    • https://beautydiction.com/ckfinder/userfiles/files/38875521631.pdfIn PDF document text
    • http://garage-ys.info/js/upload/files/dojoviliweramagifanel.pdfIn PDF document text
    • 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_off0000d980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD980 10876 bytes
SHA-256: 104a0cfab785d2339b6f4269f5c8de429a4826c5d35a5b9744880fca4a88c379
font_01_sfnt_off0000f26e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26E 18440 bytes
SHA-256: d41edd418b275db1041b892ab463704d2afe7e67c4b7fe90d870e96a483211a2
font_02_sfnt_off00012211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12211 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1