Malicious PDF — malware analysis report

Static analysis result for SHA-256 357b894878b7009a…

MALICIOUS

PDF

89.3 KB Created: 2021-08-11 04:41:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 582f47254688984000da0c3ae0ff0e73 SHA-1: c4f64bd2d6282902567f4cafae12ce3d12b548ff SHA-256: 357b894878b7009afe246dcf2068b8a9f7d72f650468811f0174330665bd514b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is often used to redirect users to malicious sites. The heuristics indicate a link farm pointing to compromised WordPress upload storage, suggesting an attempt to distribute further malware or phishing content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff67182c23---40414226585.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/4om59pg2622u3oc7n2quij143r/vixeledik.pdf
    • https://digireg.gr/upload/74963659329.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/7i01e2ta0leljlhjv131i2stuf/60941077541.pdf
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/0acd7c24015e5e8c5c0f59d5dcf79641/bozogopovuvefe.pdf
    • https://tomas-music.com/contents//files/tufifetoliwezanomesapesup.pdf
    • http://shukokai-voves.fr/userfiles/file/lalifoseralenix.pdf
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/5ebd84b59c4b46656fdbee1c45525340/fajajukogezi.pdf
    • https://pypconsultores.mx/userfiles/file/fezalovasodigutozu.pdf
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/diduzobariwusiguvupevel.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/584589b4f9ac8f758e55f56815ca5c3b/18485590623.pdf
    • http://refpecsbelvaros.hu/kepek/files/18690604858.pdf
    • https://baigiangtoanhoc.com/upload/files/41237584742.pdf
    • http://vigova.vn/Images_upload/files/bixeredubexovuguvoxaxabej.pdf
    • http://odpadykj.cz/UserFiles/File/zezot.pdf
    • http://icsbc.ru/fuploader//file/76103349350.pdf
    • http://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/39073286110.pdf
    • http://ajivikafinance.com/userfiles/file/69566115645.pdf
    • http://www.smwiarus.pl/ckfinder/userfiles/files/19398042586.pdf
    • http://3e-recycling.ru/app/webroot/filesfiles/kaxurij.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b87dbf19eb7---19616602958.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610ad171a86f9---21691045725.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=psp+3+games+free+download+full+version
    • 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_off0000f76c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF76C 16792 bytes
font_01_sfnt_off00010f83.bin
d7d1c6ccd63c3d1066972002c2a290392684c8468523481236047aa7a3b904a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F83 11168 bytes
font_02_sfnt_off0001296d.bin
95638e047cc064af48e2a830b89c939c81c174e657ae3a7eab4702e2be4f0c6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1296D 17168 bytes