Malicious PDF — malware analysis report

Static analysis result for SHA-256 76c4bd7020ad285f…

MALICIOUS

PDF

102.8 KB Created: 2021-06-29 00:20:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: de9dce38ea2acbdb471fa65f25be06df SHA-1: fe34129eb431ff96fc98db2daa4c7531b7d0ece0 SHA-256: 76c4bd7020ad285faf0ac326cb20a5a250d49f3c87c738a28eeb521a29cae494
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple potentially compromised WordPress sites, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

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://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/e168b22e507bb87347a438366d16feef/86771909453.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/1a0409c0680452e22be30c59943946d1/31189722903.pdf
    • https://dbjadow.pl/attachments/file/1816604592.pdf
    • https://imad0c0.com/js/ckfinder/userfiles/files/61889838077.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec86523ffc---46622003043.pdf
    • http://griby.biz/ckfinder/userfiles/files/10199049589.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e01b33336---75529397543.pdf
    • https://area5srl.it/file/bupuwunutatuvarizoneg.pdf
    • http://ubest.ru/images/file/zufikaxedinarudezex.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/ed382026a8ffdcc9caaf12cabcab01c1/pufazabumux.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/832aa2c0dfb21b7ffef63368061eeb92/nulut.pdf
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/4ef034741dc3a80b2165f1141e00a324/42167911798.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f4b360090---vizub.pdf
    • https://aquafilling.com/userfiles/file/wimovutivugezugibogakusuf.pdf
    • http://taskentcompany.com/userfiles/file/98388345271.pdf
    • https://etonbio.com/newsLetters/images/file/punisarelaxotaludeninaxas.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/552bd44e951c8a838f076c148e723604/1576369084.pdf
    • http://bagumul.com/file_upload/spaw_upload/file/20210606132412.pdf
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/78ef02e358c3646075f9fb693d708204/weviwazikapesimavefetagef.pdf
    • http://duquenne-moteurs.fr/webroot/upload/files/23612563654.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d81a03bf82---jelusudozujuk.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/69cgk16u5qd4h87igtefm4k1mi/ronolemidurexirejumesil.pdf
    • http://www.climatisur.com/ckfinder/userfiles/files/bizunivu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=darcy+weisbach+equation+for+head+loss
    • 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_off00012702.bin
1f37f59073e30fe7bea2bb670515103aa3cc7462e34df581e65f82ea59aaf912
pdf-font-stream PDF embedded font (sfnt) at offset 0x12702 11160 bytes
font_01_sfnt_off000140ec.bin
25779b44f7df21966b5f9878c2b5ec0554bdb0d81d116aaa1c13a74310b1f32d
pdf-font-stream PDF embedded font (sfnt) at offset 0x140EC 20080 bytes
font_02_sfnt_off00017606.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17606 16792 bytes