Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c3bf6ad0050d4e5…

MALICIOUS

PDF

88.6 KB Created: 2021-07-31 21:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce2e66eb2304c1dd1cdf0543bf5e5067 SHA-1: cf94cb581d8f6345ee57ecc892d6d3c33026265e SHA-256: 8c3bf6ad0050d4e51218814c644ec58aa303c0ce67c9471d0b646281779763d4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to compromised WordPress sites, suggesting an attempt to host malicious content or redirect users. ClamAV detection and ML classification further support its malicious nature, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9886

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://argentum.com/wp-content/plugins/super-forms/uploads/php/files/mh6rpvhk7al11qtgugoam01q5e/49429572317.pdf
    • http://www.findvoters.com/userfiles/file/56025793759.pdf
    • http://lnianemarzenie.pl/userfiles/file/xufelitinakar.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b6623cbd739---dupili.pdf
    • http://huimao.com/upload/986123847.pdf
    • http://colorfulmedia.de/fotki/fotki/file/56126903451.pdf
    • http://burragebrothers.net/demo/jolie/beta/userfiles/files/82255016896.pdf
    • http://tuvanluatdanang.com/upload/ck/files/85191027805.pdf
    • https://yourownadviser.com/ckfinder/userfiles/files/24954976093.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/1bdceedcff114eca1cdc751f0fe25112/13886375902.pdf
    • http://1982thsreunion.com/clients/a/a8/a85c6617a93da1462bf6c3e7dda9c043/File/74436136167.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/89vbnrtj5jsibbobjn03kvd3vh/jajilanamudutunef.pdf
    • http://smithmaloney.com/clients/3/32/32eae1a42220421eddab78da2f55685d/File/furavalev.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/7cbba1eb3946e768cff63c96037d0960/kimelevipugig.pdf
    • https://vivekanandbawwa.com/userfiles/file/gowubego.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/385abaffbfd5669152ce1f348b1b2b3d/12290217263.pdf
    • http://odpadykj.cz/UserFiles/File/18557268419.pdf
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/13621835561.pdf
    • http://christopherdallo.com/file/lebupireb.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160815bf9d901f---nezukewitivaxedob.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fa94761fb2e---sadagasadosizavewim.pdf
    • http://tuanlongland.com/upload/files/75918391822.pdf
    • http://walkercombsfamilyreunion.com/clients/d/df/dfd517ab040340b2551da60fba195f5f/File/wotesek.pdf
    • http://csc010.com/userfiles/file/20210705065642_lyhgg5.pdf
    • http://akiyastyle.com/app/webroot/js/ckfinder/userfiles/files/95487781525.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+use+a+venn+diagram+with+3+circles
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c262fd430b5---venixaxusupif.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_off0000efbf.bin
407daf59878a8f14b9b5b60016a21ee3200153c1273695ab1d06e29dd02fac45
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBF 18092 bytes
font_01_sfnt_off00011f43.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F43 16792 bytes
font_02_sfnt_off0001375a.bin
da1732ef66254847d60d4888291c0299e4c4d57c22fb8cad84bb7e7a442cb787
pdf-font-stream PDF embedded font (sfnt) at offset 0x1375A 11232 bytes