Malicious PDF — malware analysis report

Static analysis result for SHA-256 940e6d61136d992d…

MALICIOUS

PDF

83.7 KB Created: 2021-09-08 13:25:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa2833763b90979808e3a31a59c45819 SHA-1: 2fef010e71e833c1cd1be1b7be6fa4e09610d306 SHA-256: 940e6d61136d992d92da3a3e94799abaac52e1817cf08d55dc33f6af23753041
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external links, many of which point to compromised CMS upload directories or disposable hosting. This indicates the file is likely designed to redirect users to malicious sites or host further malware, consistent with phishing or malware distribution tactics. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://thanuyentea.com/ckfinder/userfiles/files/68566298529.pdf
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/n5csne86q54gg03r0hncrthgc1/dejatilesotatemukunu.pdf
    • http://tomei4x4.jp/js/upload/files/36008535667.pdf
    • http://pagyesa.org/userfiles/file/20210901170906.pdf
    • http://saxonrt.hu/img/userfiles/files/zeresakikerar.pdf
    • https://giridhareye.org/ckfinder/userfiles/files/zasorazutekopogovasipa.pdf
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/163057775994.pdf
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/17631397861.pdf
    • https://cdmsig.com/ckfinder/userfiles/files/wiveluwuteturodubezili.pdf
    • http://irinaburmistrova.ru/files/mopijetuxovilo.pdf
    • http://www.americaninvest.net/upls/files/rilavuvizutugep.pdf
    • http://sanfrancescovet.com/userfiles/files/66410077984.pdf
    • http://siamsnail.com/media/userfiles/files/tazukowejupikonazegusote.pdf
    • http://rfinshaat.az/userfiles/file/zifabuvowoxopuwobesogore.pdf
    • http://greenflameenergy.com/userfiles/file/22001700638.pdf
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wumuni.pdf
    • https://holcom-wd.com/webroot/img/files/dajewetuxefejaman.pdf
    • http://hak-al.com/resimler/files/lefonofurivefasusi.pdf
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/b505a06fc3fb6672673ae16659320cea/82760303057.pdf
    • http://damnoen.com/ckfinder/pho/files/tusesalikidege.pdf
    • https://ysh.my/userfiles/file/50339018915.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/9c60de0d894b6cec5789f412b7c379f4/wilojufumetotuxa.pdf
    • http://chanhungcorp.com/images/uploads/files/novoregi.pdf
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/37287823394.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=perfume+the+story+of+a+murderer+%D9%85%D8%AA%D8%B1%D8%AC%D9%85+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000bbee.bin
412799f76c2efc0e6cd2abe7b4873b695ddc05499d7451fe5e3bfb89943525d8
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xBBEE 17564 bytes
font_01_sfnt_off0000d6a6.bin
ffd6d1d974e37fad75fe59a196a0ac347f3c6cffe094dd2cd67236505338500f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A6 10736 bytes
font_02_sfnt_off0000ef6b.bin
a9601727fd0add86ff15f06f1fc9c28b7c867642acb5ac0a8932fbe670a79b33
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6B 20248 bytes
font_03_sfnt_off000123c5.bin
beca2a0fe21debc8f71e33ea1d840f6062a88697ba1401b391525d4fa704e21b
pdf-font-stream PDF embedded font (sfnt) at offset 0x123C5 17440 bytes