Malicious PDF — malware analysis report

Static analysis result for SHA-256 259bc9329acdd2c1…

MALICIOUS

PDF

97.7 KB Created: 2021-09-02 22:00:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5dbf872455db7461dfff5ddf567e56da SHA-1: 1e1a725d53846de6880e1cba5949f224c1f1de4f SHA-256: 259bc9329acdd2c1601a9eb9648cb7ce9474acf704083fe134c916d4e3a142df
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. Heuristics indicate it functions as a link farm, directing users to compromised or disposable hosting sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://tractorpulling-emmeloord.nl/upload/file/78775199303.pdf
    • http://amoy-art.com/Upload/file/mifanigevojiselaref.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd560a7553---bapov.pdf
    • http://www.park-seversk.ru/other/js/ckfinder/userfiles/files/paberuxegag.pdf
    • http://fontanarosaserigrafia.it/userfiles/file/12072881581.pdf
    • http://zubrcup.by/files/files/68933714713.pdf
    • https://hanyauntuktesting.com/contents/files/66125088344.pdf
    • http://bydnjl.com/userfiles/files/23955365711.pdf
    • http://synowka.pl/galeria/file/nifisekazuje.pdf
    • https://communeouchamps.fr/userfiles/file/lutimod.pdf
    • https://keongracun.org/contents//files/42756977888.pdf
    • https://gym-rectif.fr/ckfinder/userfiles/files/25454189266.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/k1fs473qpqtiu4rpqmgnf6dhr7/77168632032.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161003dc00cf61---takitukefuxazej.pdf
    • http://locthanhwindow.com/img_duhoc/files/8091442704.pdf
    • http://thedewakohchang.com/image/upload/File/1347282069.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b50e650d98---26909215414.pdf
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/31be1d2820adf86fe6d5a468983d2c81/wevaboziwejetedopolavag.pdf
    • http://kadet-ck.cz/pic/file/degezazulolezajajoxudifen.pdf
    • http://olympicwroclaw.pl/zdjecia/fck/file/gusegeposunelazida.pdf
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/f08a3b121c030a940957796fa1fcd3f4/gegagetur.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608165f44b0a3---65848147067.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16118ca94d7216---ditopinomido.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/u3l7kaas039lqhk1k4u9gfpos1/89294735500.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=challenging+integer+word+problems+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000114b3.bin
e4c6b79dac1eb6346e5afed627dee1f077549269b090ba77a7650696911d933d
pdf-font-stream PDF embedded font (sfnt) at offset 0x114B3 11204 bytes
font_01_sfnt_off00012e5e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5E 16792 bytes
font_02_sfnt_off00014670.bin
9c250e81481c763f14b0c4692a9a094535b97c1abb446e7bca4597d5e4dcf68d
pdf-font-stream PDF embedded font (sfnt) at offset 0x14670 19244 bytes